The barge weighs 45 000 lb and supports two automobiles A and B which weigh 4000 lb

Question:

The barge weighs 45 000 lb and supports two automobiles A and B which weigh 4000 lb and 3000 lb, respectively, if the automobiles start from rest and drive towards each other, accelerating at BA = 4 ft/s2 and an = 8 ft/s2 until they reach a constant speed of 6 ft/s relative to the barge, determine the speed of the barge just before the automobiles collide. How much time does this take? Originally the barge is at rest. Neglect water resistance.

30 ft