Someone throws his .20-kg football in the the living room and knocks over his mother's .8 kg antique vase. Ater the collision, the football bounces straight back with a speed of 3.9 m/s, while the vase is moving at 2.6 m/s in the opposite direction. a) How fast did Tyrrell throw the football? b) If the football continued to travel at 3.9 m/s in the same direction it was thrown would the vase have to be more or less massive than .8 kg? I'm not sure on how to get the Velocity of the football prior of hitting the vase. I did figure out the vase's momentum is .8 * 2.6 = 2.08 If the momentum of the football before it hit the vase was given I know it could be answer with p/m=v But I have no idea on how to get the velocity of the football prior of hitting the vase. I also dont understand the second question at all.