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9.S: The Gaseous State (Summary)
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Gasses are
compressible
because there is so much space between individual gas particles. Energy transferred from the collision of gas particles with their container exerts a
gas pressure
. In chemistry, we typically measure gas pressure using units of
atmospheres
(atm) or in
mm Hg
(also referred to as torr). One atmosphere of pressure equals exactly 760 mm Hg.
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The volume of a gas varies
inversely
with the applied pressure; the greater the pressure, the smaller the volume. This is relationship is referred to as
Boyles’s Law
. For a two-state system where the number of moles of gas and the temperature remain constant, Boyle’s Law can be expressed as
\[P_{1}V_{1}=P_{2}V_{2} \nonumber \]
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The volume of a gas varies
directly
with the absolute temperature; the higher the temperature, the larger the volume. This is relationship is referred to as
Charles’s Law
. For a two-state system where the number of moles of gas and the pressure remain constant, Charles’s Law can be expressed as: \[\frac{V_{1}}{T_{1}}=\frac{V_{2}}{T_{2}} \nonumber \]
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In this equation, the
absolute temperature
in Kelvin (K) must be used. Kelvin is defined as (degrees centigrade + 273.15). Zero degrees Kelvin is referred to as “absolute zero” and it is the temperature at which (theoretically) all molecular motion would cease.
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The volume of a gas varies
directly
with the number of moles of the gas that are present; the greater the number of moles, the larger the volume. This is relationship is referred to as
Avogadro’s Law
. For a two-state system where the temperature and the pressure of a gas remain constant, Avogadro’s Law can be expressed as: \[\frac{V_{1}}{n_{1}}=\frac{V_{2}}{n_{2}} \nonumber \]
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Because the volume of a gas varies directly with the number of moles of the gas that are present and with the absolute temperature (in Kelvin), and inversely with the pressure, the gas laws can be combined into a single proportionality; \[V\propto \left ( \frac{nT}{P} \right ) \nonumber \]
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This proportionality can be converted to an equality by inserting the proportionality constant
R
(the universal gas constant), where
R
= 0.082057 L atm mol
-1
K
-1
, and can be re-written as: \[V=R\left ( \frac{nT}{P} \right )\; \; or\; \; PV=nRT \nonumber \]
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This is referred to as the Ideal
Gas Law
and is valid for most gasses at low concentrations. For a two-state system where the identity of the gas does not change, the Ideal Gas Law can be expressed as: \[\frac{P_{1}V_{1}}{n_{1}T_{1}}=\frac{P_{2}V_{2}}{n_{2}T_{2}} \nonumber \]
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The gas constant
R,
is calculated based on the experimental observation that
exactly
one mole of any gas at
exactly
1 atm and at 0 ˚C (273 K) has a volume of
22.414 L
. The conditions, 1 atm and 0 ˚C, are called standard temperature and pressure, or
STP
.
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The ideal gas laws allow a quantitative analysis of whole spectrum of chemical reactions involving gasses. When you are approaching these problems, remember to
first
decide on the
class
of the problem:
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If it is a “single state” problem (a gas is produced at a single, given, set of conditions), then you want to use
PV
= nRT.
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If it is a “two state” problem (a gas is changed from one set of conditions to another) you want to use \[\frac{P_{1}V_{1}}{n_{1}T_{1}}=\frac{P_{2}V_{2}}{n_{2}T_{2}} \nonumber \]
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If the volume of gas is quoted at STP, you can quickly convert this volume into moles with by dividing by 22.414 L mol
-1
.


19.7: Summary
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This chapter addresses many issues involving Native peoples that are a result of the colonization of Indigenous peoples, the effects of a long history of governmental administration, and the manipulation of Native history and cultures in public spheres. Indigenous peoples in the United States today have lived through a long period of cultural collapse and are subject to extreme competition for land, rights, and resources. This chapter focuses primarily on the Indigenous peoples of Oregon within the United States. The issues faced by these people are similar to those faced by Indigenous peoples around the world, including a history of colonization, removal from traditional lands to reservations, signing away land and rights in treaties, and forced education in boarding schools. Disempowerment of tribal sovereignty, disenfranchisement from lands and resources, and forced assimilation have significantly affected Native peoples.
In addition, Indigenous peoples of the United States face significant problems adjusting to contemporary society. The general lack of education about Indigenous peoples has caused a lack of knowledge about Native history and culture in society. Within this culture, mascots and stereotypes are challenging to Native peoples, who face racism in society. Contemporary tribal nations struggle to restore cultures and governance systems. Native peoples must adjust to the cross-culturalism of modern society while they seek to maintain tribal identities and memberships in tribal nations. Scholarly studies of Native peoples are also addressed, as the studies and perceptions of anthropologists have significantly affected how tribes are perceived today.


10.3: Long-Run Outcomes
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Long Run Supply Decisions
The long-run supply curve in a perfectly competitive market has three parts; a downward sloping curve, a flat portion, and an upwards sloping curve.
learning objectives
- Describe the long-run market supply curve of a perfectly competitive market
The long-run supply curve of a market is the sum of a series of short-run supply curves in the market (). Prior to determining how the long-run supply curve looks, its important to understand short-run supply curves.
Long-run Supply Curve : As the chart demonstrates, a market’s long-run supply curve is the sum of a series of short-run supply curves in a given market.
Short-Run Supply Curves
While most people focus on the second half of a supply curve, which has a positive slope, that is not how the supply and pricing decision works in practice. As you can see from the chart, the first items that are produced start out with a very high price. This is because it is very expensive for a producer to manufacture one item. The producer has to incur fixed costs, such as learning the necessary skills to produce the item and purchasing new tools. These initial fixed costs make the cost of producing one good very expensive.
However, as more goods are produced, those initial fixed costs are spread out over more items. This decreases the price of per unit of each good produced for a period of time. As a result, in the early stages of production the supply curve is sloping downward as you can see in the chart. This period of supply is known as “increasing returns to scale,” because a proportional increase in resources yields a greater proportional increase in output.
At some point, the per unit share of fixed costs becomes less than the variable costs of producing one more item. Variable expenses include purchasing more raw materials to manufacture another item. When this occurs, the supply curve slopes upward. Thus, in the short-run, a market’s supply curve looks like an oddly shaped “u.” This period of supply is known as “decreasing returns to scale,” because a proportional increase in resources yields a smaller proportional increase in its amount in output. Between these two periods is the “constant returns to scale,” where a proportion increase in resources yields an equal proportional increase in the amount of output.
Long-Run Supply Curves
A market’s long-run supply curve is the sum of the market’s short-run supply curves taken at different points of time. As a result, a long-run supply curve for a market will look very similar to short-run supply curves for a market, but more stretched out; the long-term market curve will a wider “u.” A long-run supply curve connects the points of constant returns to scales of a markets’ short-run supply curves.; the bottom of each short-term supply curve’s “u.” Consider the attached chart.
The first short-run supply curve reflects what happens when a firm enters into a new market for the first time. When it does, it should make an economic profit. In a perfectly competitive market, firms can freely enter and exit an industry. When other business notice that the first firm is making it profit, they will enter the market to capture some of that profit and because there is nothing preventing them from doing so. In the early stages of the market, where only one or a few firms are producing goods, the market experiences increasing returns to scale, similar to what an individual firm would experience.
As more firms enter the market and time passes, production yields less and less returns in comparison to the production. Eventually the market reaches a state of constant returns to scale. How long this period of constant returns is varies by industry. Agriculture has a longer period of constant returns while technology has shorter.
Eventually, production of goods in a market yields less of a return than the amount of goods that go into product, which causes the market to enter into a period of decreasing returns to scale and the market’s supply curve slopes upward.
Long Run Market Equilibrium
The long-run equilibrium of a perfectly competitive market occurs when marginal revenue equals marginal costs, which is also equal to average total costs.
learning objectives
- Describe the long-run market equilibrium
The long-run is the period of time where there are no fixed variables of production. As with any other economic equilibrium, it is defined by demand and supply.
Demand
In a perfect market, demand is perfectly elastic. The demand curve also represents marginal revenue, which is important to remember later when we calculate quantity supplied. That means regardless of how much is produced by the suppliers, the price will remain constant.
Perfectly Elastic Demand : In a perfectly competitive market, demand is perfectly elastic.
Supply
In a perfectly competitive market, it is assumed that all of the firms participating in production are trying to maximize their profits. So a firm will produce goods until the marginal costs of production equal the marginal revenues from sales. In a perfectly competitive market in the long-term, this is taken one step further. In a perfectly competitive market, long-run equilibrium will occur when the marginal costs of production equal the average costs of production which also equals marginal revenue from selling the goods. So the equilibrium will be set, graphically, at a three-way intersection between the demand, marginal cost and average total cost curves.
Repercussions of Equilibrium
A perfectly competitive market in equilibrium has several important characteristics.
- Firms can’t make economic profit; the best they can do is break even so that their revenues equals their costs.
- The market is productively and allocatively efficient. This means that not only is the market using all of its resources efficiently, it is using its resources in a way that maximizes the social welfare.
- Economic surplus is maximized, which means there is no deadweight loss. Attempting to improve the conditions of one group would harm the interests of the other.
Productive Efficiency
Productive efficiency occurs when production of a good is achieved at the lowest resource cost possible, given the level of production of other goods.
Learning objectives
- Describe the efficiency of production in perfectly competitive markets
Productive efficiency occurs when the economy is getting maximum output from its resources. The concept is illustrated on a production possibility frontier (PPF) where all points on the curve are points of maximum productive efficiency (i.e., no more output can be achieved from the given inputs). An equilibrium may be productively efficient without being allocatively efficient. In other words, just because a market maximizes the output it generates, that doesn’t mean that social welfare is maximized.
Production Possibilities on Frontier Curve : This chart shows production possibilities for production of guns and butter. Points B, C, and D are productively efficient and point A is not. Point X is only possible if the means of production improve.
Production efficiency occurs when production of one good is achieved at the lowest resource (input) cost possible, given the level of production of the other good(s). Another way to define productive efficiency is that it occurs when the highest possible output of one good is produced, given the production level of the other good(s). In long-run equilibrium for perfectly competitive markets, productive efficiency occurs at the base of the average total cost curve, or where marginal cost equals average total cost. Productive efficiency requires that all firms operate using best-practice technological and managerial processes. By improving these processes, an economy or business can extend its production possibility frontier outward, so that efficient production yields more output.
Monopolistic companies may not be productively efficient because companies operating in a monopoly have less of an incentive to maximize output due to lack of competition. However, due to economies of scale, it may be possible for the profit-maximizing level of output of monopolistic companies to occur with a lower price to the consumer than perfectly competitive companies. So, consumers may pay less with a monopoly, but a monopolistic market would not achieve productive efficiency.
Allocative Efficiency
Free markets iterate towards higher levels of allocative efficiency, aligning the marginal cost of production with the marginal benefit for consumers.
Learning objectives
- Explain resource allocation in terms of consumer and producer surplus and market equilibrium
Allocative efficiency is the degree to which the marginal benefits consumers receive from goods are as close as possible to the marginal costs of producing them. At the optimal level of allocative efficiency in a given market, the last unit’s marginal cost would be perfectly equal to the marginal benefit it provides consumers, resulting in no deadweight loss.
The amount of value generated in a market that efficient equals the social value of the produced output minus the value of resources used in production. Optimal efficiency is higher in free markets, though reality always has some limitations and imperfections to detract from completely perfect allocative efficiency. Markets are not efficient if it is subject to:
Final goods : When an economy has allocative efficiency, it produces goods and services that have the highest demand and that society finds most desirable. For example, for the U.S. to achieve an allocative efficient market, it would need to produce a lot of coffee.
- monopolies,
- monopsonies,
- externalities,
- public goods which construe market failure, or
- price controls which construe government failure in addition to taxation.
Allocative efficiency is the main means to measure the degree markets and public policy improve or harm society or other specific subgroups.
Although there are different standards of evaluation for the concept of allocative efficiency, the basic principle asserts that in any economic system, choices in resource allocation produce both “winners” and “losers” relative to the choice being evaluated. The principles of rational choice, individual maximization, utilitarianism, and market theory further suppose that the outcomes for winners and losers can be identified, compared, and measured.
Under these basic premises, the goal of maximizing allocative efficiency can be defined according to some neutral principle where some allocations are objectively better than others. For example, an economist might say that a change in policy increases allocative efficiency as long as those who benefit from the change (winners) gain more than the losers lose.
Entry and Exit of Firms
The absence of barriers of entry and exit is a necessary condition for a market to be perfectly competitive.
Learning objectives
- Explain the entry and exit of firms in perfectly competitive markets.
Barriers to entry and exit are an important characteristics to consider when analyzing a market. In perfectly competitive markets, there are no barriers to entry or exit. This is a critical characteristic of perfectly competitive markets because firms are able to freely enter and exit in response to potential profit. Therefore, in the long-run firms cannot make economic profit but can only break even.
However, in most other types of markets barriers do exist. These types of barriers, defined below, prevent free entry to or exit from markets.
Barriers to Entry
Barriers to entry are obstacles that make it difficult to enter a given market. The term can refer to hindrances a firm faces in trying to enter a market or industry. Barriers can also be obstacles an individual faces in trying to gain entrance to a profession, such as education or licensing requirements.
Because barriers to entry protect incumbent firms and restrict competition in a market, they can distort prices. Monopolies are often aided by barriers to entry. Examples of barriers to entry include:
- Capital: need the capital to start up such as equipment, building, and raw materials.
- Customer loyalty: Large incumbent firms may have existing customers loyal to established products. The presence of established strong brands within a market can be a barrier to entry in this case.
- Economy of scale: The increase in efficiency of production as the number of goods being produced increases. Cost advantages can sometimes be quickly reversed by advances in technology.
- Intellectual property: Potential entrant requires access to equally efficient production technology as the combatant monopolist in order to freely enter a market. Patents give a firm the legal right to stop other firms producing a product for a given period of time, and so restrict entry into a market. Patents are intended to encourage invention and technological progress by guaranteeing proceeds as an incentive. Similarly, trademarks and service marks may represent a kind of entry barrier for a particular product or service if the market is dominated by one or a few well-known names.
A patent is an example of an intangible asset with a limited life : Patents are an example of intellectual property. If a firm does not own intellectual property relevant to the industry, that could prove to be a significant barrier to entry into that market.
Barriers to Exit
Barriers to exit are obstacles in the path of a firm which wants to leave a given market or industrial sector. These obstacles often cost the firm financially to leave the market and may prohibit it doing so. If the barriers of exit are significant; a firm may be forced to continue competing in a market, as the costs of leaving may be higher than those incurred if they continue competing in the market. The factors that may form a barrier to exit include:
- High investment in non-transferable fixed assets: This is particularly common for manufacturing companies that invest heavily in capital equipment which is specific to one task.
- High redundancy costs: If a company has a large number of employees, employees with high salaries, or contracts with employees which stipulate high redundancy payments, then the firm may face significant cost if it wishes to leave the market.
- Other closure costs: Contract contingencies with suppliers or buyers and any penalty costs incurred from cutting short tenancy agreements.
- Potential upturn:Firms may be influenced by the potential of an upturn in their market that may reverse their current financial situation.
Key Points
- The long-run supply curves of a market is the sum of a series of that market’s short-run supply curves.
- Most supply curves are composed of three periods of production: a period of increasing returns to scale, constant returns to scale, and decreasing returns to scale.
- A long-run supply curve connects the points of constant returns to scales of a markets’ short-run supply curves.
- In a perfectly competitive market, demand is perfectly elastic. This means the demand curve is a horizontal line.
- Once equilibrium has been achieved, firms in a perfectly competitive market can’t achieve economic profit; it can only break even.
- A perfectly competitive market in equilibrium is productively and allocatively efficient.
- An equilibrium may be productively efficient without being allocatively efficient.
- Another way to define productive efficiency is that it occurs when the highest possible output of one good is produced, given the production level of the other good(s).
- Productive efficiency requires that all firms operate using best-practice technological and managerial processes.
- Allocative efficiency occurs where a good or service’s marginal benefit is equal to its marginal cost. At this point the social surplus is maximized with no deadweight loss.
- Free markets that are perfectly competitive are generally allocatively efficient.
- Allocative efficiency is the main means to measure the degree markets and public policy improve or harm society or other specific subgroups.
- Under these basic premises, the goal of maximizing allocative efficiency can be defined according to some neutral principle where some allocations are objectively better than others.
- Barriers to entry are obstacles that make it difficult to enter a given market. The term can refer to hindrances a firm faces in trying to enter a market or industry. Barriers can be obstacles an individual faces in trying to enter into a profession, such as education or licensing requirements.
- Because firms are able to freely enter and exit in response to potential profit, this means that in the long-run firms cannot make economic profit; they can only break even.
- Barriers to exit are obstacles in the path of a firm which wants to leave a given market or industrial sector.
Key Terms
- constant returns to scale : Changes in output resulting from a proportional change in all inputs (where all inputs increase by a constant factor). If output increases by that same proportional change then there are constant returns to scale (CRS).
- decreasing returns to scale : Changes in output resulting from a proportional change in all inputs (where all inputs increase by a constant factor). If output increases by less than the proportional change then there are decreasing returns to scale.
- increasing returns to scale : The characteristic of production in which output increases by more than the proportional increase in inputs.
- long-run : The conceptual time period in which there are no fixed factors of production.
- Productive Efficiency : An economic status that occurs when when the highest possible output of one good is produced, given the production level of the other good(s).
- Allocative efficiency : A state of the economy in which production represents consumer preferences; in particular, every good or service is produced up to the point where the last unit provides a marginal benefit to consumers equal to the marginal cost of producing.
- Barriers to entry : Obstacles that make it difficult to enter a given market. The term can refer to hindrances a firm faces in trying to enter a market or industry, such as government regulation, or a large, established firm taking advantage of economies of scale.
- barriers to exit : Obstacles in the path of a firm that want to leave a market or industrial sector.
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- Perfect competition. Provided by : Wikipedia. Located at : en.Wikipedia.org/wiki/Perfect_competition . License : CC BY-SA: Attribution-ShareAlike
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3: Examining the Evidence Using Graphs and Statistics
Chapter 1 discussed what a population, sample, parameter, and statistic are, and how to take different types of samples. Chapter 2 discussed ways to graphically display data. There was also a discussion of important characteristics: center, variations, distribution, outliers, and changing characteristics of the data over time. Distributions and outliers can be answered using graphical means. Finding the center and variation can be done using numerical methods that will be discussed in this chapter. Both graphical and numerical methods are part of a branch of statistics known as descriptive statistics . Later descriptive statistics will be used to make decisions and/or estimate population parameters using methods that are part of the branch called inferential statistics .
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- 3.1: Measures of Center
- This section focuses on measures of central tendency. Many statistical question can be answered by knowing the center of the data set. There are three measures of the “center” of the data. They are the mode, median, and mean. Any of the values can be referred to as the “average.”
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- 3.2: Measures of Spread
- Variability is an important idea in statistics. Variability describes how the data are spread out. If the data are very close to each other, then there is low variability. If the data are very spread out, then there is high variability. How do you measure variability? It would be good to have a number that measures it. This section will describe some of the different measures of variability, also known as variation.
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- 3.3: Ranking
- Along with the center and the variability, another useful numerical measure is the ranking of a number. A percentile is a measure of ranking. It represents a location measurement of a data value to the rest of the values. Many standardized tests give the results as a percentile. Doctors also use percentiles to track a child’s growth.


10.1: Introduction
Genetics is the study of heredity. Johann Gregor Mendel set the framework for genetics long before chromosomes or genes had been identified, at a time when meiosis was not well understood. Mendel selected a simple biological system and conducted methodical, quantitative analyses using large sample sizes. Because of Mendel’s work, the fundamental principles of heredity were revealed. We now know that genes, carried on chromosomes, are the basic functional units of heredity with the capability to be replicated, expressed, or mutated. Today, the postulates put forth by Mendel form the basis of classical, or Mendelian, genetics. Not all genes are transmitted from parents to offspring according to Mendelian genetics, but Mendel’s experiments serve as an excellent starting point for thinking about inheritance.
Contributors and Attributions
Remixed and/or curated from the following works:
Clark, M. A., Douglas, M., & Choi, J. (2018). 3.2.1 Introduction . In Biology 2e . OpenStax (CC BY 4.0; Access for free at https://openstax.org/books/biology-2e/pages/1-introduction ).


1: Introduction
What is art?: For this course, a work of art is the visual expression of an idea or experience, formed with skill , through the use of a medium.
What is a medium?: A medium is a material, along with its accompanying technique. (The plural is media.) When a medium is used in such a way that the object or performance contributes to our understanding or enjoyment of life, we experience the final product as art.
How do we evaluate art? There are two ways to evaluate art. One approach is to analytically critique the work using the recognized art elements as well as the principles of art (aka principles of design). The art elements are 1. Line 2. Value 3. Color 4. Shape 5. Form 6. Space and 7. Texture. The principles of art are more numerous and include Perspective, Balance, Emphasis, Composition, Repetition, Variety, Unity, Contrast, Movement, Light, Pattern, Proportion, Size and Scale, and Surface.
A second part of art evaluation is to study the context of the work. In this case we use the Ws of detective work. What was created? Who created the work? When was it created? Why was it created? When we have a better understanding of the times and circumstances the artist experienced, the better we can appreciate the art. Was the work created during a time of war? Was it created as a form of protest? Was the art created as propaganda, possibly supporting the ruler or political party of the time? These are all important questions to ask as we evaluate artwork. The evolution of painting, sculpture, and architecture is the story of artists who experienced life in their time, often facing hardships we can only imagine. These are often brave individuals devoted to their craft and following their creative calling. By pushing art forward, they have broadened the definition of fine art in our time.


6.2: Sources to Meet Needs
To Learn Background Information
When you first get a research assignment and perhaps for a considerable time afterward, you will almost always have to learn some background information as you develop your research question and explore how to answer it.
Sources from any category and from any subgroup within a category – except journal articles – can meet your need to learn background information and understand a variety of perspectives. Journal articles are usually too specific to be background information. From easy-to-understand to more complex sources, read and/or view those that advance your knowledge and understanding.
For instance, especially while you are getting started, secondary sources that synthesize an event or work of art and tertiary sources such as guidebooks can be a big help. Wikipedia is a good tertiary source of background information.
Sources you use for background information don’t have to be sources that you cite in your final report, although some may be.
One important reason for finding background information is to learn the language that professionals and scholars have used when writing about your research question. That language will help you later, particularly when you’re searching for sources to answer your research question.
To identify that language, you can always type the word glossary and then the discipline for which you’re doing your assignment in Google.
Here are two examples to try:
Putting a phrase in quotes in most search boxes ensures that the phrase will be searched rather than individual words.
To Answer Your Research Question
You have to be much pickier with sources to meet this need because only certain choices can do the job. Whether you can use quantitative or qualitative data depends on what your research question itself calls for.
Only primary and secondary sources can be used to answer your research question and those need to be professional and/or scholarly sources for most disciplines (humanities, social sciences, and sciences). But the arts often require popular sources as primary or secondary sources to answer research questions. Also, the author’s purpose for most disciplines should be to educate and inform or, for the arts, to entertain and perhaps even to sell. Keep in mind that primary sources are those created at the same time as an event you are researching or that offer something original, such as an original performance or a journal article reporting original research. Secondary sources analyze or otherwise react to secondary sources. Because of the information lifecycle, the latest secondary sources are often the best because their creators have had time for better analysis and more information to incorporate.
Example: Quantitative or Qualitative Data
Suppose your research question is “How did a particular king of Saudi Arabia, King Abdullah, work to modernize his country?”
That question may lend itself to qualitative descriptive judgments—about what are considered the components of modernization, including, for instance, what were his thoughts about the place of women in society.
But it may also be helped by some quantitative data, such as those that would let you compare the numbers of women attending higher education when Abdullah became king and those attending at the time of his death or, for instance, whether manufacturing increased while he reigned.
So looking for sources that provide both quantitative and qualitative information (not necessarily in the same resource) is usually a good idea.
If it is not clear to you from the formats of sources you are assigned to read for your course, ask your professor which formats are acceptable to your discipline for answering your research question.
Sources to Answer Your Research Question
- Quantitative or Qualitative: Will be determined by the question itself.
- Fact or Opinion: Professional and scholarly for most disciplines; the arts often use popular, as well.
- Scholarly, Professional, or Popular: Professional and scholarly for most disciplines; the arts often use popular, as well.
- Primary, Secondary, or Tertiary: Primary and secondary.
- Publication Format: Those acceptable to your discipline.
To Convince Your Audience
Convincing your audience is similar to convincing yourself and it takes the same kinds of sources—as long as your audience is made up of people like you and your professor, which is often true in academic writing. That means using many of those sources you used to answer your research question.
 Perhaps you will include more that are secondary sources rather than primary, some that are popular or professional rather than scholarly, and some whose author intent may not be to educate and inform.
 If you have a different audience, use what is convincing to them.
 If you have a different audience, you may be better off including some sources intended to entertain or sell.
- Scholarly, Professional, or Popular: Those with the same expertise level as you used to answer the question if your audience is like you and your professor. If you have a different audience, you may be better off including some popular sources.
 If you have a different audience, you may be better off including more secondary sources than primary.

To Describe the Situation
Choosing what kinds of sources you’ll need to meet this need is pretty simple—you should almost always use what’s going to be clear and compelling to your audience. Nonetheless, sources intended to educate and inform may play an out-sized role here.
But even then, they don’t always have to educate and inform formally , which opens the door to using sources such as fiction or the other arts and formats that you might not use with some other information needs.
Sources to Describe the Situation
- Quantitative or Qualitative: Whatever you think will make the description most clear and compelling and your question important to your audience.
- Fact or Opinion: Often to educate and inform, but sources don’t have to do that formally here, so they can also be to entertain or sell.
- Scholarly, Professional, or Popular: Whatever you think will make the description most clear and compelling and your question important to your audience.
- Primary, Secondary, or Tertiary: Whatever you think will make the description most clear and compelling and your question important to your audience. Some disciplines will not accept tertiary for this need.
- Publication Format: Whatever you think will make the description most clear and compelling and your question important to your audience. Some disciplines will accept only particular formats, so check for your discipline.
To Report What Others Have Said
The choices here about kinds of sources are easy: just use the same or similar sources that you used to answer your research question that you also think will be the most convincing to your audience. Look for sources about how others have treated your research question
Exercise: Name the type of source
An interactive H5P element has been excluded from this version of the text. You can view it online here:
https://minnstate.pressbooks.pub/ctar/?p=79#h5p-13


20.14: TV Violence
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Learning Objectives
- Does Television Viewing Encourage Aggression in Children?
Research conducted by
Mariana Fernandez, University of Houston-Downtown undergraduate
Case study prepared by
Nichole Rivera
Overview
How much television is too much for children? Television advocates espouse the educational benefits that children may reap from instructive programming. However, many researchers say that excess television watching may contribute to aggressive behavior in children. Young boys, in particular may be susceptible to this effect. What are the effects, if any, on children’s behavior when television is used as a babysitter?
In a survey of University of Houston-Downtown students, parents reported their children's age, characteristic behavior, and television viewing habits. Convenience sampling was used to gather \(30\) subjects (\(N=30\)).
Questions to Answer
Is there a relationship between hours of television watched and child's obedience? Will a child be more or less aggressive if he/she watches a lot of television?
Design Issues
This survey offered a very limited sample (\(N=30\)), which was further hindered by reporting participants’ filling out an individual survey for each individual child. This contributes to some lack of true variability in responses because participants tended to report similar behavior for each child. This may magnify errors associated with self-reported data. The sample would provide greater reliability if each participant reported on only one child’s behavior.
The survey has broad questions which do not provide much context for reported behaviors. In some instances aggression may be positively rated, but this survey treats all aggression as a negative characteristic. In addition, the instrument itself measures largely nominal data, making in depth analysis difficult.
Descriptions of Variables
| Variable | Description |
| TV hours | Total number of TV hours watched per day |
| Obedience |
How obedient the child is
1 = very obedient, 5 = not obedient |
| Attitude |
Attitude while playing with other children
1 = non-aggressive, 5 = very aggressive |
Data Files
TV.xls
Links
TV Guide - Mighty Morphin' Power Rangers v. Teenage Mutant Ninja Turtles
References
- Boyatzis, Chris J. and Matillo Gina M. (1995). Effects of "The Mighty Morphin Power Rangers" on Children's Aggression with Peers. Child Study Journal, 25 (1), 45-57.
- Charlton, Davie. (2001). Monitoring Children's Behavior in Remote Community Before and Six Years After the Availability of Broadcast TV. North America Journal of Psychology, 3, 429-441.
- Huesmann, Rowell L., Moise-Titus, Jessica, Podolski, Cheryl-Lynn, Eron, Leonard D. (2003). Longitudinal Relations Between Children's Exposure to TV Violence and their Aggressive and Violent Behavior in Young Adulthood: 1977-1992. Developmental Psychology 39(2), 201-221.
- Troseth, Georgene L. (2003). TV Guide: Two-Year-Old Children Learn to Use Video as a Source of Information. Developmental Psychology 39 (1), 140-150.


34.5: Thiazide and Thiazide-Like Diuretics
By the end of this section, you should be able to:
- 34.5.1 Identify the characteristics of thiazide and thiazide-like diuretic drugs used for fluid volume excess and renal system disorders.
- 34.5.2 Explain the indications, actions, adverse reactions, and interactions of thiazide and thiazide-like diuretic drugs used for fluid volume excess and renal system disorders.
- 34.5.3 Describe nursing implications of thiazide and thiazide-like diuretic drugs used for fluid volume excess and renal system disorders.
- 34.5.4 Explain the client education related to thiazide and thiazide-like diuretic drugs used for fluid volume excess and renal system disorders.
Introduction and Use
The thiazide and thiazide-like diuretics treat hypertension and edema. They are considered first-line therapies for hypertension, although their antihypertensive effects are not well understood. They treat edema related to congestive heart failure, cirrhosis, and acute and chronic renal diseases, including nephrotic syndrome, acute glomerulonephritis, and chronic renal failure. Thiazide and thiazide-like diuretics are frequently used in combination with other antihypertensives and diuretic types.
Thiazide and thiazide-like diuretics have three major properties: inhibition of sodium reabsorption, increased reabsorption of calcium, and creation of mild extracellular fluid losses:
- Thiazide and thiazide-like diuretics inhibit the reabsorption of sodium in the distal convoluted tubule by competing with chloride on the Na-Cl transporter, resulting in the loss of chloride and the passive loss of sodium; however, the therapy decreases reabsorption of only 3%–5% of the sodium in the filtrate. This transporter is similar to the NKCC in the loop of Henle. The drugs also exert some inhibitory effect on sodium reabsorption in the proximal tubules and the collecting ducts; however, this diuretic action is countered by the additional reabsorption of sodium in the same area of the nephron.
- Thiazide and thiazide-like diuretics increase the rate of calcium reabsorption in two ways. First, the drugs directly increase the reabsorption rate of calcium that normally occurs in the distal tubule. Second, the drugs decrease extracellular fluid volume by limiting reabsorption of sodium, and this volume change indirectly triggers increased calcium reabsorption into the proximal tubule.
- Thiazide and thiazide-like diuretics block sodium reabsorption from the distal convoluted tubule; this can result in hyponatremia, which increases water loss. The drugs also create mild extracellular fluid loss, which can decrease the tubular volume in the loop of Henle, resulting in decreased free water loss.
Hydrochlorothiazide is one of the most commonly used diuretics. Metolazone is a thiazide-like diuretic that, unlike the thiazide drugs, is also effective in chronic renal disease because it does not affect the GFR. In addition, metolazone does not trigger the RAAS, which means that the use of metolazone combined with a loop diuretic can minimize diuretic resistance and increase renal response with fewer adverse effects (Bond et al., 2022). Chlorthalidone is a thiazide-like diuretic with prolonged action (48–72 hours).
Table 34.7 lists common thiazide and thiazide-like diuretics and typical routes and dosing for adult clients.
| Drug | Routes and Dosage Ranges |
|---|---|
| Hydrochlorothiazide ( Hydrodiuril , Microzide ) |
Hypertension:
Initial dose: 25 mg orally once daily; may increase dose to 50 mg/day in 1–2 divided doses.
Edema: 25–100 mg orally daily as a single or divided dose; administration on alternate days or 3–5 days per week may also be effective. |
|
Chlorothiazide
( Diuril ) |
Edema: 500–1000 mg IV once or twice daily. |
|
Metolazone
( Zaroxolyn ) |
Edema:
5–20 mg orally once daily.
Hypertension: 2.5–5 mg orally once daily. |
|
Chlorthalidone
( Thalitone ) |
Hypertension:
25 mg orally daily; start with lowest dose and titrate to response.
Edema: 25 mg orally daily; start with lowest dose and titrate to response. |
Adverse Effects and Contraindications
The adverse effects of thiazide diuretics are related to the sodium losses and the ionic imbalance created by those losses (Akbari & Khorasani-Zedah, 2022). Adverse effects include metabolic alkalosis, hypercalcemia, hyperglycemia, hyperuricemia, hyperlipidemia, photosensitivity reactions, hyponatremia due to decreased reabsorption, and hypokalemia due to action of the sodium–potassium pump in the distal convoluted tubule. Their photosensitizing effects also appear to increase the risk of skin cancer (Shin et al., 2019).
Thiazide and thiazide-like diuretics are contraindicated in individuals with sulfonamide allergy. Sensitivity reactions occur most commonly in clients who experience frequent allergic reactions and less commonly than previously believed in sulfa-sensitive clients. Reactions can include rash, hives, angioedema, wheezing, and anaphylaxis (Akbari & Khorasani-Zedah, 2022). Thiazide and thiazide-like diuretics can increase the risk of digoxin toxicity, and the drugs also should not be administered with lithium. Thiazide and thiazide-like diuretics should be used with caution in clients with renal disease and are contraindicated for clients who are anuric.
Table 34.8 is a drug prototype table for thiazide and thiazide-like diuretics featuring hydrochlorothiazide. It lists drug class, mechanism of action, adult dosage, indications, therapeutic effects, drug and food interactions, adverse effects, and contraindications.
|
Drug Class
Thiazide and thiazide-like diuretics Mechanism of Action Exact mechanism unknown, but affects electrolyte reabsorption at the distal renal tubule Increases excretion of sodium and chloride |
Drug Dosage
Hypertension: Initial dose: 25 mg orally once daily; may increase dose to 50 mg/day in 1–2 divided doses. Edema: 25–100 mg orally daily as a single or divided dose; administration on alternate days or 3–5 days per week may also be effective. |
|
Indications
Edema related to congestive heart failure, cirrhosis, and acute and chronic renal diseases, including nephrotic syndrome, acute glomerulonephritis, and chronic renal failure Hypertension Therapeutic Effects Decreased edema Decreased blood pressure |
Drug Interactions
Lithium Nonsteroidal anti-inflammatory drugs (NSAIDs) Corticosteroids Antidiabetic drugs Food Interactions Alcohol |
|
Adverse Effects
Electrolyte imbalances Hypotension (including orthostatic hypotension) Renal dysfunction Photosensitivity reactions Erythema multiforme, including Stevens–Johnson syndrome Aplastic anemia |
Contraindications
Sulfa sensitivity Anuria |
Safety Alert
Thiazide Diuretics
Thiazide diuretics increase the risk for photosensitivity reactions. The client should avoid long periods of sun exposure and should always use sunscreen.
(Source: DailyMed, Hydrochlorothiazide , 2018)
Unfolding Case Study
Part B
Read the following clinical scenario to answer the questions that follow. This case study is a follow-up to Case Study Part A.
Gordon Jefferson completes his diagnostic evaluation, and the health care provider diagnoses him with edema. He follows up with his health care provider 1 week later to get the results of his diagnostic studies and review his treatment plan. He is prescribed metolazone 10 mg once daily by mouth for his edema.
Decreased urine output
- Answer
-
Eat a low-potassium diet.
Nursing Implications
The nurse should do the following for clients taking thiazide or thiazide-like diuretics:
- Assess the client’s blood pressure before giving the initial dose and then intermittently during drug therapy on an ongoing basis.
- Monitor for evidence of cardiac changes by assessing heart rate and ECG rhythm strips.
- Evaluate the client’s response to therapy as evidenced by decreased edema.
- Monitor the client’s urine output and laboratory tests for electrolyte imbalances.
- Assess and monitor the client for other adverse effects, drug and food interactions, and contraindications.
- Provide client teaching regarding the drug and when to call the health care provider. See below for additional client teaching guidelines.
Clinical Tip
Accurate Assessment of Client’s Fluid Volume Status
Clients with heart failure are often hospitalized to correct fluid volume overload . Nurses are responsible for accurate physical assessment, data collection, and documentation of the client’s fluid volume status, which is critical for effective diuretic therapy. The nurse should monitor the client’s response to treatment by measuring urine output, monitoring their weight daily, auscultating lung sounds for rales or crackles, and assessing the client’s lower extremities and other dependent areas to determine whether the edema is decreasing.
(Source: Malik et al., 2022)
Client Teaching Guidelines
The client taking a thiazide or thiazide-like diuretic should:
- Follow a balanced diet with moderate intake of potassium-rich foods.
- Wear sunscreen and avoid excessive sun exposure because of risk for photosensitivity reactions.
The client taking a thiazide or thiazide-like diuretic should not:
- Take nonsteroidal anti-inflammatory drugs.
Unfolding Case Study
Part C
Read the following clinical scenario to answer the questions that follow. This case study is a follow-up from Case Study Parts A and B.
Gordon Jefferson is following up with the health care provider 3 months after his initial diagnosis of edema. He reports that the swelling in his legs has improved; however, he is now reporting generalized weakness. The health care provider examines the client and reviews the chemistry panel results from laboratory work drawn earlier in the morning. Gordon says he has been taking his prescribed medications:
Current Medications
Losartan 50 mg orally daily
Dapagliflozin 10 mg orally daily
Metolazone 10 mg orally daily
| Vital Signs | Physical Examination | Chemistry Panel | |
|---|---|---|---|
| Temperature: | 98.0°F |
|
Sodium:
140 mEq/L
Potassium: 2.9 mEq/L BUN : 24 mg/dL Creatinine: 1.4 mg/dL eGFR: 40 mL/minute/1.73 m 2 |
| Blood pressure: | 138/88 mm Hg | ||
| Heart rate: | 76 beats/min | ||
| Respiratory rate: | 16 breaths/min | ||
| Oxygen saturation: | 98% on room air | ||
| Height: | 5'9" | ||
| Weight: | 191 lb |
The health care provider diagnoses the client with hypokalemia, prescribes a potassium supplement, and recommends a low-sodium diet with potassium-rich foods.
The nurse provides teaching about the new diet to Gordon. Which of the following statements by Gordon indicates a need for further teaching?
- Answer
-
“I will limit my intake of green vegetables.”
When reviewing Gordon’s medications, the nurse should remind him to immediately report which of the following symptoms?
- Answer
-
A slower than normal heart rate


17.5: Pacing
The Principles of Management textbook contains sixteen modules—roughly one module per week for a sixteen-week semester. If you need to modify the pace to cover the material more quickly or create a 12 week course design, the following modules work well together:
- Module 3: Planning and Mission and Module 4: Environments and Strategic Management
- Module 8: Groups, Teams, and Teamwork and Module 12: The Individual and the Organization
- Module 10: Leadership and 13: Ethics in Business
If you are teaching this course in an eight-week session, you could combine the following modules.
- Module 1: Introduction to Management and Module 2: History of Management
- Module 3: Planning and Mission and Module 4: Environments and Strategic Management
- Module 5: Decision Making and Module 6: Organization Structures
- Module 7: Human Resource Management and Module 11: Motivation
- Module 8: Groups, Teams, and Teamwork and Module 12: The Individual and the Organization
- Module 9: Culture and Diversity and Module 16: Globalization and Business
- Module 14: Communication and Module 15: Control
Contributors and Attributions
CC licensed content, Original
- Pacing. Provided by : Lumen Learning. License : CC BY: Attribution
CC licensed content, Shared previously
- Stopwatch. Authored by : Adrien Coquet, FR. Provided by : Noun Project. Located at : https://thenounproject.com/term/stopwatch/1094680/ . License : CC BY: Attribution


1.3: The Demand Schedule
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The demand schedule is the relationship between own-quantity demanded and corresponding own-price levels. Several variables could affect the demand for a product, including the prices or quantities of related goods. The adjective “own-quantity” is used to mean the quantity of the product being analyzed. For example, the own-quantity of beef could be represented as \(Q_{BEEF}\) and the own-price of beef as \(P_{BEEF}\). The price of pork, \(P_{PORK}\), could conceivably affect demand for beef, but this is not the own-price of beef. The point to be made is that the demand schedule is the relationship between the product’s own-quantity and its own-price holding all other variables that could affect demand constant at some fixed value. The normal convention in this course will be to use subscripts to denote the product in question. For example, \(Q_{1}\) refers to the demand for good 1, \(P_{2}\) refers to the price of good 2, etc.
The demand schedule can be expressed mathematically as \(Q_{1} = f P_{1}\) or \(P_{1} = f^{-1} (Q_{1})\). The term “direct demand” is used when \(Q_{1}\) is on the left-hand side of the equation and the term “inverse demand” when \(P_{1}\) is on the left-hand side. When showing a demand relationship as an equation, the normal practice is to express the relationship in terms of direct demand. However, it will generally be graphed in inverse form with the price of the product on the vertical axis and the quantity on the horizontal axis. This convention is consistent with most microeconomics text books and can be useful when you want to simultaneously show production (supply side) relationships on the same plot. Many textbooks, however, do not distinguish between direct and inverse demand. The distinction is being made here because you learned back in middle-school algebra that if \(y = f(x)\), then \(y\) goes on the vertical axis and \(x\) goes on the horizontal. The term “inverse demand,” permits adherence to both algebraic and economic conventions.
Demonstration \(\PageIndex{1}\): An inverse market demand schedule
The Law of Demand
The law of demand states that quantity and price are negatively related. In other words, if the price of the product increases, then the quantity demanded will decrease and vice versa . The law of demand reflects two phenomena. First, consumer preferences generally exhibit diminishing marginal utility. Diminishing marginal utility is a technical way of saying that consumers receive lower amounts of additional satisfaction from each additional unit of a product they consume. Because of diminishing marginal utility, the price will need to fall to induce consumers to buy more units of products that they already consume. This contributes to the negative relationship between quantity demanded and price. Second, in most cases, different consumers place different valuations on the same product. For example, suppose that Jane and John Doe would both enjoy tickets to a St. Louis Cardinals baseball game. Jane loves baseball and is a huge Cardinals fan. John mildly enjoys baseball and prefers the Minnesota Twins. It would stand to reason that Jane would probably place a higher value on the tickets than John would. The point here is that it is often the case that some consumers are very enthusiastic about a product and are willing to participate in the market even when the price is high. Other, less enthusiastic, consumers stay out of the market at high prices but are willing to participate once the price comes down a bit. For this reason, the number of consumers willing to participate in the market increases as the price falls and decreases as the price rises. This also contributes to the negative relationship between quantity demanded and price.
Because of diminishing marginal utility and differences in valuation across consumers, an increase (decrease) in price has two potential effects, each of which contributes to the negative relationship between quantity and price.
- Each consumer buys less (more) of the product due to diminishing marginal utility.
- The total number of consumers decreases (increases) as consumers with valuations close to the prevailing price exit (enter) the marketplace.
Demand Shifters
The demand schedule characterizes the relationship between quantity demanded and that product’s own-price. For instance, the demand schedule for beef would show the relationship between quantity of beef demanded and the price of beef holding everything else constant. What happens if something else changes? There are other prices that could affect the demand for beef. For many consumers, pork or poultry serve as reasonable substitutes for beef. Consequently, if pork or poultry prices decline (rise) relative to beef prices, one would expect reduced (increased) quantities of beef to be demanded. This suggests that other factors, aside from a product’s own-price, need to be considered. These other factors are called demand-shift variables. If the value of a shift variable changes, you will need to plot a new demand schedule that reflects the updated relationship between quantity demanded and the product’s own-price. The following are some common demand shift variables.
Prices of related goods (substitutes or complements)
Related goods in demand are classified as substitutes in consumption or complements in consumption. A substitute in consumption is a good that the consumer can use instead of the good in question to meet his or her underlying want or need. For example, if you are analyzing the demand schedule for beef, then chicken, pork, or fish are all reasonable substitute products. After all, one could order a chicken, pork, or seafood entree from the menu in lieu of beef; or the supermarket shopper may decide to cook chicken breasts, pork chops, or fish fillets for dinner instead of beef. Formally, product 2 is considered to be a substitute for product 1 if an increase (decrease) in the price of product 2 causes an increase (decrease) in the demand schedule for product 1. In other words, there is a positive relationship between the price of product 2 and the quantity of product 1 that consumers demand.
A complement in consumption is a good that the consumer uses along with the good in question. For example, if you are analyzing the demand for sport utility vehicles (SUVs), then gasoline is reasonable complementary product. After all, an SUV is a large automobile and uses a lot of gas. In recent years, gasoline prices appear to have had an effect on the demand schedule for SUVs. During periods of high gasoline prices, sales of SUVs suffer. Formally, product 2 is considered to be a complement for product 1 if an increase (decrease) in the price of product 2 causes a decrease (increase) in the demand schedule for product 1. In other words, there is a negative relationship between the price of product 2 and the quantity of product 1 that consumers demand.
Consumer income
Consumer incomes can also shift the demand schedule, but the direction and magnitude of the shift depend on the characteristics of the good in question. Some goods are classified as normal goods. Consumption of a normal good increases as income increases. Formally, good 1 is said to be a normal good if an increase (decrease) in income causes an increase (decrease) in the demand schedule for good 1. In other words, there is a positive relationship between consumption of good 1 and the amount of income available to consumers. Other goods are classified as inferior goods. Consumption of an inferior good decreases as income increases. Formally, good 1 is said to be an inferior good if an increase (decrease) in income causes an decrease (increase) in the demand schedule for good 1. In other words, there is a negative relationship between consumption of good 1 and the amount of income available to consumers. It is important to emphasize that the adjective “inferior” only refers to the income relationship and does not imply that the consumer dislikes the good in question.
Tastes and preferences
Demand is subject to trends, fashions, health concerns, and a variety of other considerations. For example, in 2012, media coverage of lean finely textured beef (LFTB), characterized as “pink slime”, had an impact on demand for ground beef. This would classify as information that led to an unfavorable change in preferences (meaning the product in question is less favored by consumers than before). Conversely, a growing number of studies linking blueberries to improved health has impacted demand for blueberries in a positive way. This would classify as a favorable change in preferences.
- Link to a 2012 magazine article on the LFTB controversy by economists J. Ross Pruitt and David P. Anderson ( visit choicesmagazine.org ).
- Link to the 2012 ABC News Segment on LFTB mentioned in the magazine article ( visit youtube.com ).
- Link to LSU AgCenter publication Blueberries and Your Health ( visit lsuagcenter.com ).
Population
Market demand reflects the sum of all consumers in the marketplace. All else equal, as the number of consumers increases (decreases), the demand schedule will increase (decrease).
Demonstration \(\PageIndex{2}\): Demand shift variables change the demand schedule
Demand Schedules from a Linear Demand Relationship
A general demand relationship would need to include all the demand shifters that could affect demand in addition to own-price. With this in mind, consider the following demand equation for good A:
\(Q_{A} = 20Pop + 0.01M + 2P_{B}- 4P_{A}\)
In this equation, \(Q_{A}\) is the quantity of good A in thousands of units, \(Pop\) is population in millions of persons, \(M\) is disposable income in dollars, \(P_{B}\) is the price of good B in dollars, and \(P_{A}\) is the price of good A in dollars. Given this equation, you are able to answer some general questions about the demand for good A.
- Is good A a normal good or an inferior good? How can you tell? Good A is a normal good. You can tell because the coefficient associated with the income variable (0.01) is a positive number. If this were a negative number, you would have an inferior good.
- Is good B a substitute or a complement to good A? How can you tell? Good B is a substitute for good A. You can tell because the coefficient associated with the price of good B is a positive number. If this were a negative number, you would instead conclude that good B is a complement to good A.
- Does the demand for good A conform to the law of demand? How can you tell? Yes. The coefficient associated with the price of good A is a negative number showing an inverse relationship between the quantity of good A and the price of good A.
- What variables shift the demand schedule? In this case, there are three variables: population \(Pop\), income \(M\), and the price of the substitute good \(P_{B}\). Remember that the demand schedule is the relationship between own-price and own-quantity. In the equation above, \(P_{A}\) represents the own-price and \(Q_{A}\) represents the own-quantity. Thus, every right-hand-side variable other than \(P_{A}\) is a demand shifter.
The demand schedule shows the relationship between own-price and own-quantity demanded holding all else constant. In this case, “all else” consists of the three demand shifters. Thus, to get an equation for the demand schedule you need to fix these shift variables at some value. Let us use a value of 3 million for \(Pop\), $30,000 for \(M\), and $20 for \(P_{2}\). Using these values, you get the direct demand schedule:
\(Q_{A} = 20(3) + 0.01(30000) + 2(20) -4P_{A}\)
or
\(Q_{A} = 400-4P_{A}\)
Remember that this is the direct demand schedule because \(Q_{A} = f(P_{A})\). It is simple enough to get the inverse demand schedule. Simply solve to get \(P_{A}\) on the left side of the equation. The inverse demand schedule is
\(P_{A} = 100 - \dfrac{1}{4} Q_{A}\)


16.2: Contact Information
| Instructor: | Jessica Kelly |
| Course Number: | SC 113 |
| Mailing Address: | 100 Reservoir Road , Herkimer, NY 13350 |
|
Ways to communicate with me and other students: |
The general practice in SLN is for communication to take place within the online course. There are several ways to communicate with me and other students: Discussion Forums are where you post your responses to discussion questions and read the responses of others. Your contribution to discussions is an important part of the course, and part of the learning activities you’ll be evaluated on. Forums are located within the Learning Modules. Use this space for any question or comment that is of interest for the whole class. Course Mail , is available in the “Communications” tab; ‘course mail’ is a private one-on-one way for you to communicate with me. Use course mail to address specific questions or comments to me or selected members of the class. Use this resource only for private communication. ‘Talk with the Professor/ Ask a Question’ are areas in the course for public contact and communication with me and others in the course. These areas are found within each module of the course and are specific to the content of each module in which they are found. The Bulletin Board , found at the bottom of the main Learning Modules course page, is a public area in the course for contact and communication with the entire class that is not tied to the content in a specific course module. |
| Phone: |<PHONE_NUMBER> ext. 8222 |
| Private Communications: | Contact me through ANGEL Course Mail |
| Logon Schedule: | I will logon frequently and do my best to respond to all questions within 48 hours |
Contributors and Attributions
- Contact Information. Authored by : Kelly, Jessica. Provided by : Herkimer College. Located at : herkimer.sln.suny.edu/section/default.asp?id=201640%2DHER%2DNS%2DSC%2D113%2DV1. Project : ATD Course. License : CC BY: Attribution


3.1: Abstract
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… the course was conceived on the basis of two ideas—“Classroom without Walls” and “Global Village”. – Charles Quist-Adade (2008)
This chapter presents preliminary overview and findings of a pilot course webconferencing course on Globalization involving largely students and instructors in Canada and Ghana. The overview will focus more on the planning and implementation stages of the course than on the delivery and content. It will highlight the challenges confronted, lessons learned, and lessons unlearned throughout the more than two years planning and implementation of the project, whose principal objective was to create geographically distributed collaborative learning and teaching between students and faculty in developed and developing countries.
The undergraduate and graduate course on Globalization (Sociology of Global Inequalities), which was implemented in the Spring of 2008 (from January 7 to April 21), was conceived on the basis of two ideas— “Classroom without Walls” and “Global Village”. It was designed, using a unique interactive multimedia approach to link students and faculty in two international locations—Ghana and Canada. The course, through the integrative information and educational technologies, aimed to break the boundaries of time, space, and distance thereby facilitating the sharing of knowledge between the students at the three sites. What is more, it sought to create a “networked collaborative learning environment” for students and instructors at the University of Ghana and Kwantlen University College in British Columbia, Canada.
The partially online course used a mixed mode delivery approach, combining synchronous video-audio streaming (videoconferencing), real chat, online materials, pre-packaged online materials, as well as asynchronous chat sessions. The course had a classroom component at each of the host sites that was supported by a course website. Interaction between learner and lecturer was primarily through text messaging and online chats during synchronous lecture sessions. Students also had to use online chat sessions and discussion forums with teaching assistants.
The course had a mix of synchronous and asynchronous activities (i.e., some activities took place at the same time, same place; some at the same time, different place; and some at a different time, different place). The course provided continuous feedback, high levels of interaction and an emphasis on student work and group projects.
In all 31 undergraduate students from Kwantlen University College (KUC) and six graduate students from the University of Ghana, Legon (UGL) took the course. The preliminary study showed that while the preparatory stage was quite daunting and the project leader had some harrowing experiences in finding collaborators, accessing funding, the overall benefits of the project to both students and instructors were quite substantial, making the efforts and sacrifices worthwhile.


3.3.2: Intentional Torts and Negligence
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Civil suits arise from damages suffered by one or more persons or entities at the hands of another person or entity. The damage can happen in a variety of circumstances, and may be intentional or unintentional. Unlike criminal cases, civil suits seek to provide some form of remedy for the loss suffered by an injured party. Civil suits are decided by judges and juries based on the specific situation, especially when violation of statutes , or laws, is not in question.
Torts
Civil suits involve different causes of action, and they are included in one general classification: torts . The word “tort” means “wrong” in French. Thus, torts are wrongs committed against others who suffer some form of damage as a result. While these damages could also be the result of criminal action, the criminal element of the matter is not tried in a civil lawsuit. The standard of proof is lower for civil suits, and a finding of liability in a tort case does not necessarily translate to guilt in a criminal case.
The actor of the wrongs has historically been called a tortfeasor . When a wrong is committed by a tortfeasor, damage is done to another. Tort law seeks to address this damage based on the circumstances of the issue, which is based on fault . Civil lawsuits are used by the injured parties to seek redress for the loss associated with the tort. Unlike criminal proceedings, redress is often provided in the form of money as opposed to incarceration. As such, the burden of proof of fault is lower. The offender , or tortfeasor, who commits the act is the accused in a civil suit. The plaintiff , who is the injured party, files the lawsuit on which the civil court will make a decision. The offender ultimately becomes the defendant , who must respond to the accusations of the plaintiff in a civil suit.
During tort litigation, the judge and jury have certain separate functions (Kionka, 2013):
| The Judge Decides Issues of Law | The Jury Decides Questions of Fact |
|---|---|
| The duty of the defendant to the plaintiff, if any | What happened |
| The elements of the defense | Legal consequences of what happened |
| Application of legal rules | The damages suffered by the plaintiff |
Harm
Two types of torts are intentional torts and negligence. Intentional torts occur as the result of a conscious and purposeful act. Negligence occurs when an individual does not exercise duty of care. Torts are acts or omissions that result in injury or harm to an individual in such a way that it leads to a civil wrong that occurs as liability (WEX, n.d.). In tort law, harm can be defined as a loss or disadvantage suffered as a result of the actions or omissions of another (WEX, n.d.). This loss can be physical harm, such as slipping and falling on a wet floor, or personal property harm, such as allowing water to ruin furniture. The damage is the result of what someone else did, or did not do, either intentionally or based on a lack of reasonable care.
There are two basic elements to torts: damages and compensation (Laws, tort.laws.com). Tort law acts to compensate persons who have suffered damages at the hands of another (Baime, 2018). Tort law determines the legal responsibility of the defendant and the value of the harm. Different types of torts look at different types of circumstances.
Intentional Torts
Intentional torts are committed by an offender who understands that he or she is committing a tort. Intent does not always equate to directly causing an end result. In some cases, the intent may be something else, such as the possession of knowledge that some harm may occur. The harm may result from intentional action, or due to some circumstance that the offender feels will be excusable (Kionka, 2013).
Some circumstances that could allow the defendant to argue that the action is excusable would include: permission by the injured party, or defense of property, self, or another person (Kionka, 2013). If the injured party agrees to allow the defendant to juggle knives and one slips and causes harm, the action might be excusable to some extent. If a defendant caused harm to the plaintiff’s car while trying to avoid being hit by the car, it would likely be excusable.
Different types of intentional torts are based on different circumstances and face different remedies , or means of recovering losses (Baime, 2018):
- Assault is an intentional tort that occurs when an individual has a reasonable apprehension of an intentional act that is designed to cause harm to himself or herself, or to another person.
- Malicious prosecution occurs when an individual files groundless complaints to initiate a criminal matter against another.
- Defamation occurs when an individual intentionally creates and promotes malicious falsehoods about another. Defamation can occur in two ways: slander and libel. Slander is, in effect, when falsehoods are spoken. Libel occurs when falsehoods are expressed in written or other recorded forums.
- Invasion of privacy involves unwanted production of negative public information. Different standards apply to invasion of privacy based on the status of the individual as a public figure.
Negligence
Negligence is another type of tort that has two meanings. It is the name of a cause of action in a tort, and it is a form of conduct that does not meet the reasonable standard of care (Kionka, 2013). The cause of action is the reason for the damage, and the standard of care is based on the care that a reasonable person would need in a given situation. Negligence is decided by determining the duty of the defendant, whether or not the defendant committed a breach of that duty, the cause of the injury, and the injury itself.
For an action to be deemed negligent, there must be a legal duty of care , or responsibility to act, based on the reasonable standard in a situation (Baime, 2018). An individual can be considered negligent if he agreed to watch a child, but did not do so, and then harm came to the child. An individual would not be considered negligent if he did not know that he was supposed to watch the child, or did not agree to watch the child.
A reasonable person is defined as someone who must exercise reasonable care based on what he or she knows about the situation, how much experience he or she has with the situation, and how he or she perceives the situation (Kionka, 2013). In some cases, this knowledge could be based on common knowledge of community matters, such as knowing that a bridge is closed for repairs.
In some cases, the duty of care is based on a special relationship , which is a relationship based on an implied duty of care. This implied duty of care often comes about as a duty to aid , or a duty to protect another, e.g., a nurse caring for patients in a hospital, or a lifeguard being responsible for swimmers in the guarded area (Baime, 2018). A passerby does not have a duty to aid, but if the individual tries to help, then he or she is responsible for acting responsibly.
The elements of a negligence cause of action are (Kionka, 2013):
- A duty by the defendant to either act or refrain from acting
- A breach of that duty, based on a failure to conform to the standard of care by the defendant
- A causal connection between the defendant’s action or inaction, and the injury to the plaintiff
- Measurable harm that can be remedied in monetary damages
Foreseeability
Negligence case decisions are influenced by whether or not a defendant could have predicted that an action or inaction could have resulted in the tort, or foreseeability (Baime, 2018). Responsibility is often based on whether or not the harm caused by an action or inaction was reasonably foreseeable , which means that the result was fairly obvious before it occurred (Baime, 2018). A person assisting an inebriated individual into her car could be considered negligent due to the likelihood that harm would come to her while she is driving in an intoxicated state. This situation is an example of the foreseeable probability of harm .
Conclusion
Intentional torts and negligence arise based on intentional and unintentional acts committed by individuals. Damages are decided in civil courts by first determining fault and harm, and then by assigning a remedy. Sometimes, the damage can be excused if the circumstances indicate that the defendant acted with permission, or in his or her own defense. The main standard used to make a decision is the reasonable standard of care: what would a reasonable person do?
Contributors and Attributions
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The OpenStax name, OpenStax logo, OpenStax book covers, OpenStax CNX name, and OpenStax CNX logo are not subject to the creative commons license and may not be reproduced without the prior and express written consent of Rice University. For questions regarding this license, please contact<EMAIL_ADDRESS>. Download for free at https://openstax.org/details/books/b...w-i-essentials .


2.3: Models and Applications
- Set up a linear equation to solve a real-world application.
- Use a formula to solve a real-world application.
Josh is hoping to get an \(A\) in his college algebra class. He has scores of \(75\), \(82\), \(95\), \(91\), and \(94\) on his first five tests. Only the final exam remains, and the maximum of points that can be earned is \(100\). Is it possible for Josh to end the course with an \(A\)? A simple linear equation will give Josh his answer.
Many real-world applications can be modeled by linear equations. For example, a cell phone package may include a monthly service fee plus a charge per minute of talk-time; it costs a widget manufacturer a certain amount to produce x widgets per month plus monthly operating charges; a car rental company charges a daily fee plus an amount per mile driven. These are examples of applications we come across every day that are modeled by linear equations. In this section, we will set up and use linear equations to solve such problems.
Setting up a Linear Equation to Solve a Real-World Application
To set up or model a linear equation to fit a real-world application, we must first determine the known quantities and define the unknown quantity as a variable. Then, we begin to interpret the words as mathematical expressions using mathematical symbols. Let us use the car rental example above. In this case, a known cost, such as \($0.10/mi\), is multiplied by an unknown quantity, the number of miles driven. Therefore, we can write \(0.10x\). This expression represents a variable cost because it changes according to the number of miles driven.
If a quantity is independent of a variable, we usually just add or subtract it, according to the problem. As these amounts do not change, we call them fixed costs. Consider a car rental agency that charges \($0.10/mi\) plus a daily fee of \($50\). We can use these quantities to model an equation that can be used to find the daily car rental cost \(C\).
\(C=0.10x+50 \tag{2.4.1}\)
When dealing with real-world applications, there are certain expressions that we can translate directly into math. Table \(\PageIndex{1}\) lists some common verbal expressions and their equivalent mathematical expressions.
| Verbal | Translation to Math Operations |
|---|---|
| One number exceeds another by a | \(x,x+a\) |
| Twice a number | \(2x\) |
| One number is \(a\) more than another number | \(x,x+a\) |
| One number is a less than twice another number | \(x,2x−a\) |
| The product of a number and \(a\), decreased by \(b\) | \(ax−b\) |
| The quotient of a number and the number plus \(a\) is three times the number | \(\dfrac{x}{x+a}=3x\) |
| The product of three times a number and the number decreased by \(b\) is \(c\) | \(3x(x−b)=c\) |
- Identify known quantities.
- Assign a variable to represent the unknown quantity.
- If there is more than one unknown quantity, find a way to write the second unknown in terms of the first.
- Write an equation interpreting the words as mathematical operations.
- Solve the equation. Be sure the solution can be explained in words, including the units of measure.
Find a linear equation to solve for the following unknown quantities: One number exceeds another number by \( 17\) and their sum is \( 31\). Find the two numbers.
Solution
Let \( x\) equal the first number. Then, as the second number exceeds the first by \(17\), we can write the second number as \( x +17\). The sum of the two numbers is \(31\). We usually interpret the word is as an equal sign.
\[\begin{align*} x+(x+17)&= 31\\ 2x+17&= 31\\ 2x&= 14\\ x&= 7 \end{align*}\]
\[\begin{align*} x+17&= 7 + 17\\ &= 24\\ \end{align*}\]
The two numbers are \(7\) and \(24\).
Find a linear equation to solve for the following unknown quantities: One number is three more than twice another number. If the sum of the two numbers is \(36\), find the numbers.
- Answer
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\(11\) and \(25\)
There are two cell phone companies that offer different packages. Company A charges a monthly service fee of \($34\) plus \($.05/min\) talk-time. Company B charges a monthly service fee of \($40\) plus \($.04/min\) talk-time.
- Write a linear equation that models the packages offered by both companies.
- If the average number of minutes used each month is \(1,160\), which company offers the better plan?
- If the average number of minutes used each month is \(420\), which company offers the better plan?
- How many minutes of talk-time would yield equal monthly statements from both companies?
Solution
a.
The model for Company A can be written as \( A =0.05x+34\). This includes the variable cost of \( 0.05x\) plus the monthly service charge of \($34\). Company B’s package charges a higher monthly fee of \($40\), but a lower variable cost of \( 0.04x\). Company B’s model can be written as \( B =0.04x+$40\).
b.
If the average number of minutes used each month is \(1,160\), we have the following:
\[\begin{align*} \text{Company A}&= 0.05(1.160)+34\\ &= 58+34\\ &= 92 \end{align*}\]
\[\begin{align*} \text{Company B}&= 0.04(1,1600)+40\\ &= 46.4+40\\ &= 86.4 \end{align*}\]
So, Company B offers the lower monthly cost of \($86.40\) as compared with the \($92\) monthly cost offered by Company A when the average number of minutes used each month is \(1,160\).
c.
If the average number of minutes used each month is \(420\), we have the following:
\[\begin{align*} \text{Company A}&= 0.05(420)+34\\ &= 21+34\\ &= 55 \end{align*}\]
\[\begin{align*} \text{Company B}&= 0.04(420)+40\\ &= 16.8+40\\ &= 56.8 \end{align*}\]
If the average number of minutes used each month is \(420\), then Company A offers a lower monthly cost of \($55\) compared to Company B’s monthly cost of \($56.80\).
d.
To answer the question of how many talk-time minutes would yield the same bill from both companies, we should think about the problem in terms of \((x,y)\) coordinates: At what point are both the \(x\)-value and the \(y\)-value equal? We can find this point by setting the equations equal to each other and solving for \(x\).
\[\begin{align*} 0.05x+34&= 0.04x+40\\ 0.01x&= 6\\ x&= 600 \end{align*}\]Check the \(x\)-value in each equation.
\(0.05(600)+34=64\)
\(0.04(600)+40=64\)
Therefore, a monthly average of \(600\) talk-time minutes renders the plans equal. See Figure \(\PageIndex{2}\).
Find a linear equation to model this real-world application: It costs ABC electronics company \($2.50\) per unit to produce a part used in a popular brand of desktop computers. The company has monthly operating expenses of \($350\) for utilities and \($3,300\) for salaries. What are the company’s monthly expenses?
- Answer
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\(C=2.5x+3,650\)
Using a Formula to Solve a Real-World Application
Many applications are solved using known formulas. The problem is stated, a formula is identified, the known quantities are substituted into the formula, the equation is solved for the unknown, and the problem’s question is answered. Typically, these problems involve two equations representing two trips, two investments, two areas, and so on. Examples of formulas include the area of a rectangular region,
\[A=LW \tag{2.4.2}\]
the perimeter of a rectangle,
\[P=2L+2W \tag{2.4.3}\]
and the volume of a rectangular solid,
\[V=LWH. \tag{2.4.4}\]
When there are two unknowns, we find a way to write one in terms of the other because we can solve for only one variable at a time.
It takes Andrew \(30\; min\) to drive to work in the morning. He drives home using the same route, but it takes \(10\; min \) longer, and he averages \(10\; mi/h\) less than in the morning. How far does Andrew drive to work?
Solution
This is a distance problem, so we can use the formula \(d =rt\), where distance equals rate multiplied by time. Note that when rate is given in \(mi/h\), time must be expressed in hours. Consistent units of measurement are key to obtaining a correct solution.
First, we identify the known and unknown quantities. Andrew’s morning drive to work takes \(30\; min\), or \(12\; h\) at rate \(r\). His drive home takes \(40\; min\), or \(23\; h\), and his speed averages \(10\; mi/h\) less than the morning drive. Both trips cover distance \(d\). A table, such as Table \(\PageIndex{2}\), is often helpful for keeping track of information in these types of problems.
| \(d\) | \(r\) | \(t\) | |
|---|---|---|---|
| To Work | \(d\) | \(r\) | \(12\) |
| To Home | \(d\) | \(r−10\) | \(23\) |
Write two equations, one for each trip.
\[d=r\left(\dfrac{1}{2}\right) \qquad \text{To work} \nonumber\]
\[d=(r-10)\left(\dfrac{2}{3}\right) \qquad \text{To home} \nonumber\]
As both equations equal the same distance, we set them equal to each other and solve for \(r\).
\[\begin{align*} r\left (\dfrac{1}{2} \right )&= (r-10)\left (\dfrac{2}{3} \right )\\ \dfrac{1}{2r}&= \dfrac{2}{3}r-\dfrac{20}{3}\\ \dfrac{1}{2}r-\dfrac{2}{3}r&= -\dfrac{20}{3}\\ -\dfrac{1}{6}r&= -\dfrac{20}{3}\\ r&= -\dfrac{20}{3}(-6)\\ r&= 40 \end{align*}\]
We have solved for the rate of speed to work, \(40\; mph\). Substituting \(40\) into the rate on the return trip yields \(30 mi/h\). Now we can answer the question. Substitute the rate back into either equation and solve for \(d\).
\[\begin{align*}d&= 40\left (\dfrac{1}{2} \right )\\ &= 20 \end{align*}\]
The distance between home and work is \(20\; mi\).
Analysis
Note that we could have cleared the fractions in the equation by multiplying both sides of the equation by the LCD to solve for \(r\).
\[\begin{align*} r\left (\dfrac{1}{2} \right)&= (r-10)\left (\dfrac{2}{3} \right )\\ 6\times r\left (\dfrac{1}{2} \right)&= 6\times (r-10)\left (\dfrac{2}{3} \right )\\ 3r&= 4(r-10)\\ 3r&= 4r-40\\ r&= 40 \end{align*}\]
On Saturday morning, it took Jennifer \(3.6\; h\) to drive to her mother’s house for the weekend. On Sunday evening, due to heavy traffic, it took Jennifer \(4\; h\) to return home. Her speed was \(5\; mi/h\) slower on Sunday than on Saturday. What was her speed on Sunday?
- Answer
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\(45\; mi/h\)
The perimeter of a rectangular outdoor patio is \(54\; ft\). The length is \(3\; ft\) greater than the width. What are the dimensions of the patio?
Solution
The perimeter formula is standard: \(P=2L+2W\). We have two unknown quantities, length and width. However, we can write the length in terms of the width as \(L =W+3\). Substitute the perimeter value and the expression for length into the formula. It is often helpful to make a sketch and label the sides as in Figure \(\PageIndex{3}\).
Now we can solve for the width and then calculate the length.
\[\begin{align*} P&= 2L + 2W\\ 54&= 2(W+3)+2W\\ 54&= 2W+6+2W\\ 54&= 4W+6\\ 48&= 4W\\ W&= 12 \end{align*}\]
\[\begin{align*} L&= 12+3\\ L&= 15 \end{align*}\]
The dimensions are \(L = 15\; ft\) and \(W = 12\; ft\).
Find the dimensions of a rectangle given that the perimeter is \(110\; cm\) and the length is \(1\; cm\) more than twice the width.
- Answer
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\(L=37\; cm\), \(W=18\; cm\)
The perimeter of a tablet of graph paper is \(48\space{in.}^2\). The length is \(6\; in\). more than the width. Find the area of the graph paper.
Solution
The standard formula for area is \(A =LW\); however, we will solve the problem using the perimeter formula. The reason we use the perimeter formula is because we know enough information about the perimeter that the formula will allow us to solve for one of the unknowns. As both perimeter and area use length and width as dimensions, they are often used together to solve a problem such as this one.
We know that the length is \(6\; in\). more than the width, so we can write length as \(L =W+6\). Substitute the value of the perimeter and the expression for length into the perimeter formula and find the length.
\[\begin{align*} P&= 2L + 2W\\ 48&= 2(W+6)+2W\\ 48&= 2W+12+2W\\ 48&= 4W+12\\ 36&= 4W\\ W&= 9 \end{align*}\]
\[\begin{align*}L&= 9+6\\ L&= 15 \end{align*}\]
Now, we find the area given the dimensions of \(L = 15\; in\). and \(W = 9\; in\).
\[\begin{align*} A&= LW\\ A&=15(9)\\ A&= 135\space{in.}^2 \end{align*}\]
The area is \(135\space{in.}^2\).
A game room has a perimeter of \(70\; ft\). The length is five more than twice the width. How many \(ft^2\) of new carpeting should be ordered?
- Answer
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\(250\space{ft}^2\)
Find the dimensions of a shipping box given that the length is twice the width, the height is \(8\; \) in, and the volume is \(1,600\space{in.}^3\).
Solution
The formula for the volume of a box is given as \(V =LWH\), the product of length, width, and height. We are given that \(L =2W\), and \(H =8\). The volume is \(1,600\; \text{cubic inches}\).
\[\begin{align*} V&= LWH\\ 1600&= (2W)W(8)\\ 1600&= 16W^2\\ 100&= W^2\\ 10&= W \end{align*}\]The dimensions are \(L = 20\; in\), \(W= 10\; in\), and \(H = 8\; in\).
Analysis
Note that the square root of \(W^2\) would result in a positive and a negative value. However, because we are describing width, we can use only the positive result.
Access these online resources for additional instruction and practice with models and applications of linear equations.
- Problem solving using linear equations
- Problem solving using equations
- Finding the dimensions of area given the perimeter
- Find the distance between the cities using the distance = rate * time formula
- Linear equation application (Write a cost equation)
Key Concepts
- A linear equation can be used to solve for an unknown in a number problem. See Example .
- Applications can be written as mathematical problems by identifying known quantities and assigning a variable to unknown quantities. See Example .
- There are many known formulas that can be used to solve applications. Distance problems, for example, are solved using the \(d = rt\) formula. See Example .
- Many geometry problems are solved using the perimeter formula \(P =2L+2W\), the area formula \(A =LW\), or the volume formula \(V =LWH\). See Example , Example , and Example .


10.5: Summary
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Developing an IS can be costly and a complex process to manage a group of professionals to deliver a new system on time and budget. There are several development models from the formal SDLC process to more informal processes such as agile programming or lean methodologies to provide a framework to manage all the phases from start to finish.
Software development is about so much more than programming. Programming languages have evolved from very low-level machine-specific languages to higher-level languages that allow a programmer to write software for a wide variety of machines. Most programmers work with software development tools that provide them with integrated components to make the software development process more efficient.
For some organizations, building their own software applications does not make the most sense; instead, they choose to purchase or rent software built by a third party to save development costs and speed implementation. In end-user computing, software development happens outside the information technology department. When implementing new software applications, organizations need to consider several different types of implementation methodologies.
An organization’s responsibilities to complete a software development do not end with the deployment of the software. It now includes a clear and systemic process to maintain and protect customers’ and projects’ data to address security and privacy concerns.