The man A has a weight of 100 lb and jumps from rest onto the platform P that has a weig...

The man A has a weight of 100 lb and jumps from rest onto the platform P that has a weight of 60 lb. The platform is mounted on a spring, which has a stiffness k = 200 lb/ft. if the coefficient of restitution between the man and the platform is e = 0.6, and the man holds himself rigid during the motion, determine the required height h of the jump if the maximum compression of the spring is 2 ft.