Which of these are created by changing magnetic and electric fields? 1.) radiations which travel with different speeds 2) compressions which travel with different speeds 3) transverse waves which travel with the speed of light 4) longitudinal waves which travel with the speed of sound

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.