A cue stick hits a cue ball horizontally a distance x above the centre of the ball, as in the diagram below. The cue ball is on a smooth horizontal surface. You may assume that the cue ball is a solid uniform sphere and use the above given expression for its moment of inertia.

a. Find the value of x for which the cue ball will roll without slipping.

b.How does the cue ball move if x is subsequently increased by a small amount, and why?