4.) The starting lever in a pinball machine is attached to a coiled spring having a spring constant of 600 Mm. A 0.250 kg steel ball is positioned in contact with the spring. The spring is capable of elongating 0.150 m before it breaks contact with the ball. The lever releases the spring, sending the ball rolling forward with speed v1 where it collides with an identical steel ball at rest inside the game. If ball 1 has a speed of 3.00 m/s after it rebounds off ball 2, what is ball 2's final velocity? Neglect friction. Hint: v1 mav be obtained by the conservation of energy transfer of PEspring into KEhall