Two spheres of mass M1 and M2 are arranged one above the other as shown. They are separated by a fraction of a mm. They are released from rest and allowed to fall to the ground, a distance h = 7.0 m below. Mass M2 collides elastically with the ground and then elastically with mass M1. Calculate the maximum height the center of M1 rises above the ground after the collision. D = 20 cm, d = 5 cm, M1 = 0.14 kg, M2 = 1.10 kg.