Slowed traffic—E. A two-lane highway carries cars traveling at an average speed of 60 mph. In a construction zone, where the cars have merged into one lane, the average speed is 20 mph and the average...

Slowed traffic—E. A two-lane highway carries cars traveling at an average speed of 60 mph. In a construction zone, where the cars have merged into one lane, the average speed is 20 mph and the average distance between front bumpers of successive cars is 25 ft. What is the average distance between front bumpers in each lane of the two-lane section? Why? How many cars per hour are passing through the construction zone?