In the figure, block 1 of mass m1 slides from rest along a frictionless ramp from height h = 2.1 m and then collides with stationary block 2, which has mass m2 = 5m1. After the collision, block 2 slides into a region where the coefficient of kinetic friction ?k is 0.55 and comes to a stop in distance d within that region. What is the value of distance d if the collision is (a) elastic and (b) completely inelastic?