A5.25-g block starts from rest at the top of a frictionless hill that is inclined 21.0º with respect to the horizontal. The hill is125 m long. At the bottom of the hill, the surface is level and the coefficient of kinetic friction between the surface and the block is now 0.00655. (a) How far does theblock glide along the horizontal portion of the surface before coming to rest? (b) If there were no friction on the horizontal surface at the bottom of the hill, but instead a spring(k = 1250 N/m) was located 15.0 m along the horizontal surface from the bottom of the hill, how far would the spring be compressed when the block strikes it before the block comes to astop?