Problem - CP21 A disk of mass m and radius r is at- tached to a horizontal massless spring with force con- stant & as shown at right. The disk has sufficient friction with the surface that it rolls without slipping. The equi- librium position is at x = 0. At time f = 0, the center of the disk is at x = 0, and has velocity Up to the right. Find (a) the angular frequency of oscillation of the disk about its equilibrium position; (b] the amplitude of oscillation; (c) the maximum frictional force between the disk and the surface