A toy cannon uses a spring to project a 5.27 g soft rubber ball. The spring is originally compressed by 4.90 cm and has a force constant of 7.90 N/m. When the cannon is fired, the ball moves 14.4 cm through the horizontal barrel of the cannon, and there is a constant frictional force of 0.0311 N between the barrel and the ball.
(a) With what speed does the projectile leave the barrel of the cannon?
(b) At what point does the ball have maximum speed? from its original position)
(c) What is this maximum speed? I did get part A to be 1.38m/s but i cant figure out B or C.