What was the velocity ms of the ball before it was caught

Question

1. A 64 kg man on a lake of ice catches a 1 kg ball. The ball and man each move at 3 cm/s after the ball is caught. What was the velocity (m/s) of the ball before it was caught? What energy was lost in the process? (J)
2. A 165 g rock traveling south at 10 m/s strikes a 2 kg block initially at rest. If the two stick together on collision, what is their common velocity?(m/s) What energy was lost in the collision? (J)
3. A 29 kg child stands on a frictionless surface. The father throws a 0.8 kg football with a velocity of 19 m/s. What is their combined velocity if they stick together after impact?(m/s)
4. A 5 kg bowling ball collides head on with 1.8 kg pin. The pin moves forward at 2 m/s and the ball slows to 1.3 m/s. What was the initial velocity of the bowling ball?