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A road borders a rectangular forest, and a car is driven around it. The car starts from rest at one corner and accelerates at [math]120[/math] miles per hour per hour until it reaches the next corner [math]15[/math] minutes later. The second side is [math]20[/math] miles long and the car is driven along it at constant velocity equal to the final velocity reached on the first side. The car continues at this same speed on the third side. On the fourth side, however, the car slows down with constant acceleration and comes to a stop at its original starting place. Find

• the dimensions of the rectangle.
• the acceleration on the fourth side.
• the time taken for the whole trip.