1. A member of the volleyball team spikes the ball. During this process, she changes the velocity of the ball from 3.5 m/s to ?23.8 m/s along a certain direction. If the impulse she delivers to the ball is ?6.9 kg · m/s, determine the mass of the volleyball.
2. When a golfer tees off, the head of her golf club which has a mass of 160 g is traveling 58 m/s just before it strikes a 46-g golf ball at rest on a tee. Immediately after the collision, the club head continues to travel in the same direction but at a reduced speed of 48 m/s. Neglect the mass of the club handle and determine the speed of the golf ball just after impact.