A 56g steel ball is released from rest and falls vertically onto a steel plate. The ball strikes the plate and is in contact with it for .5ms. The ball rebounds elastically, and returns to its original height. The time interval for a round trip is 8.00s. In this situation, the average force exerted on the ball during contact with the plate is closest to: A) 4390 N B) 10,260 N C) 5870 N D) 7300 N E) 8780 N I was wondering what formula I should use to solve the problem.