A bibliography is a list of works (books, articles, films, etc.) on a particular topic. Annotated bibliographies tell more about the work you are citing. An annotation can both describe and evaluate a source.An annotated bibliography includes a paragraph following each citation that summarizes the work.
A frequency polygon is a graphical display of a frequency table. The intervals are shown on the X-axis and the number of scores in each interval is represented by the height of a point located above the middle of the interval.The points are connected so that together with the X-axis they form a polygon.A frequency table and a relative frequency polygon for response times in a study on weapons and aggression are shown below. The times are in hundredths of a second.Frequency polygons are useful for comparing distributions.he intervals are shown on the X-axis and the number of scores in each interval is represented by the height of a point located above the middle of the interval. The points are connected so that together with the X-axis they form a polygon.
The number of cycles per second (Hertz) (abbreviated as, hz) of anything that oscillates is called the frequency. The electricity of an AC wall outlet is said to have a frequency of 60 Hertz as it cycles negative then positive 60 times each second. Sound is an oscillating wave, but it has a broad range of frequencies. A low frequency sound (say, 50 hz) might sound like a low rumble, while a high frequency sound (say 12,000 hz), might sound more like a sizzle. A person with normal hearing can hear all the way up to about 20,000 hz.