A train has a length of 82 m and starts from rest with a constant acceleration at time t = 0 s. At this instant, a car just reaches the end of the train. The car is moving with a constant velocity. At a time t = 18 s, the car just reaches the front of the train. Ultimately, however, the train pulls ahead of the car, and at time t = 36 s, the car is again at the rear of the train. Find the magnitudes of the following quantities.
(a) the car's velocity ?
(b) the train's acceleration?