Jarod is at the state fair playing some of the games. At one booth he throws a 0.50kg ball forward with a velocity of 21.0 m/s in order to hit a 0.20 kg bottle sitting on the shelf. When it gets hit, the bottle goes flying forward at 30m/s
a. What is the velocity of the ball after it hits the bottle?
b. If the bottle were more massive, how would this affect the final velocity of the ball?