Types of Variables. It is very important when designing a research study that the researcher fully understands the variables in the study in order for the results to be valid and have meaning. A variable is something in the study that can be changed such as a characteristic or a value. The most common types of variables, especially when study cause and effect relationships, are the independent and dependent variables. The independent variable is the one that can be controlled or manipulated.
What's the maximum speed you can travel on a freeway with a 65 mph speed limit and be absolutely guaranteed not to get a speeding ticket? 65 mph. That's why it's called a speed limit. Any faster and you will be violating the statute which sets the limit. Now... is it likely you'll get stopped and cited at 66 mph?
A speed limit of 30 mph in urban areas and 35 mph on unpaved rural roads is enforced. The speed limit for county paved roads is 45 mph. All other 2 lane roads are limited to 55 mph. The interstate limit is 70 mph while other 4 lane highways are limited to 65 mph.