You and your friends are doing physics experiments on a frozen pond that serves as a frictionless, horizontal surface. Sam, with mass 80.0 , is given a push and slides eastward. Abigail, with mass 56.0 , is sent sliding northward. They collide, and after the collision Sam is moving at 38.0 north of east with a speed of 6.20 and Abigail is moving at 21.0 south of east with a speed of 8.20 .
1. What was the speed of each person before the collision?
Sam's speed:
Abigail's speed:
2. By how much did the total kinetic energy of the two people decrease during the collision?