24. A 78 g steel ball is released from rest and falls vertically onto a rigid surface. The ball strikes the surface and is in contact with it for 0.5 ms. The ball rebounds elastically, and returns to its original height
during a round trip of 4 s. Assume that the surface does not deform during contact. What is the
maximum elastic energy stored by the ball? (Use acceleration due to gravity g = 10 m/s2)
A. 23.1)
B. 43)
C. 11.5 J
D. 15.6)