I NEED SOMEONE TO HELP ME WITH THIS ONE PLEASE!! -Car A that has a mass of 2000 kg is moving at 8 m·s-1 to the west. It collides with Car B that has a mass of
4000 kg moving at 1 m-s-1 to the east. Calculate the velocity of car B, if car A moves with a velocity of 4 m. s-1
After the collision.

In a game of pool, ball a is moving with a velocity v0 of magnitude v0 = 15 ft/s when it strikes balls b and c, which are at rest and aligned as shown. knowing that after the collision the three balls move in the directions indicated and assuming frictionless surfaces and perfectly elastic impact (that is, conservation of energy), determine the magnitudes of the velocities va, vb, and vc.