Pls provide specific solutions and answers

Around 30% of professional soccer players, as well as many amateur players, suffer permanent headaches, memory loss and other ill effects due to "heading" the ball. Lets explore the physics of the forces! Sam heads a soccer ball during a soccer match. The ball is traveling horizontally with a velocity of 20 m/s when it hits her head, and rebounds in the direction it came from with a velocity of 20 m/s. In the following you can ignore gravity, air resistance and the movement of Sam's head. Also, if you wish, you can assume that the force acting on the ball is constant throughout the impact. This 30 second video shows a player heading a ball in slow motion: https://www.youtube.com/watch?v=5VroNiXG8X4 (a) Sketch the velocity-time curve of the ball that covers the time before, during and after the impact with Sam's head. (4 marks) (b) Identify the forces in the system, including any action-reaction pairs. Explain in terms of Newton's laws why a "harder" soccer ball (e.g. a ball pumped to higher pressure) of the same mass and travelling at the same velocity would be likely to exert a bigger average force on Sam's head during the impact