Consider the car-caravan analogy from Section 4 in Chapter 1. In this problem, assume a propagation speed of 75 km/hr and that each toll booth takes 15 seconds to service a car.

a) Suppose the caravan of 10 cars travels a total of 100 km beginning immediately in front of the first toll booth, travels 50 km to a second toll booth, then another 50 km to a third toll booth, and finally stops immediately after the third tool booth. What is the total end-to-end delay?

b) Where is the last car in the caravan after 45 minutes? Your answer must include a distance/specific location, and not only a relative direction.