Derek is training for a half-marathon. his training plan sets his goal for this week at 18 miles with three short runs and one longer run. his three short runs total 9.35 miles. how long will his long run need to be to meet his goal? enter your answer in the box.

Two cars which are 40 miles apart start moving simultaneously in the same direction with constant speeds. if the speed of the car which is behind is 56 mph and the speed of the other car is 48 mph, how many hours will it take for the car which is behind to catch up the car ahead of it?