A small, solid sphere of mass 0.2 kg and radius 40 cm rolls without slipping along the track consisting of slope and loop-the-loop with radius 1.5 m at the end of the slope. It starts from rest near the top of the track at a height h, where h is large compared to 40 cm. What is the minimum value of h (in terms of the radius of the loop R) such that the sphere completes the loop?