A golf ball slides down a pipe from the upper level of a miniature golf course and heads directly for the hole on the green. Unfortunately, another
player's ball is directly in the way. The second ball, which is initially
at rest, moves forward with a speed of 3.0 m/s, causing it to land
in the cup. The first ball comes to a complete stop after the collision.
Both balls have a mass of 45 g. What is the first ball's speed before the
collision