An accident investigators can tell approximately how fast a car was traveling by the skid mark it leaves after an emergency stop. Assuming you have a dry road and normal wear on the tires, they use the equation s=21d−−−√ where d is the length of the skid in feet, and s is the speed of the car. 1) (2 points) An officer investigating an accident finds a skid mark 135 feet long. Approximately how fast was the car going when the driver applied the brakes? (round to nearest mph)

2) (3 points) Drake is driving 65 mph when he sees a deer and hits the brakes. How many feet will his car cover before it comes to a complete stop? (round to nearest foot)

3. (2 points) What is a reasonable domain and range for this situation?

4. (3 points) If you double the length of the skid, does that mean the speed is doubled too? Justify your answer with a table, graph, or equation.