Example 1:Safety experts are trying to determine how long it takes a specific brand of car to come to a complete stop. They have determined that the speed of the car has a large impact on how long it takes to come to a complete stop. They decide to gather data by having the car go 10, 30, 50, 70, and 90 miles per hour and then determine how many feet it takes to come to a complete stop at each of these speeds.

What is the explanatory and response variables in this example?