A 0.500-kg block rests on a horizontal, frictionless surface. The block is pressed back against a spring having a constant of k 5 625 N/m, compressing the spring by 10.0 cm. Then the block is released. (a) Find the maximum distance d the block travels up the frictionless incline angle theta is 30.0. (b) How fast is the block going at half its maximum height? Please explain why we have to set both vi and vf=0 (final and initial velocity=0)