Two cars have a race. Car A drives with constant speed of 20 m/s. Car B
drives with speed 10 m/s for 3 s, then accelerates uniformly to a speed
of 25 m/s during the next 3 s. Car B maintains the speed of 25 m/s for
the rest of the race.
What is the minimum length of race if Car B is to overtake car A?