Question

The angle of repose θ is related to the height h and base radius r of the conical pile by the equation θ= cot^- 1 r/h .
79. When deicing salt is stored in a pile 14 feet high, the diameter of the base of the pile is 45 feet.
(a) Find the angle of repose for deicing salt.
(b) What is the base diameter of a pile that is 17 feet high?
(c) What is the height of a pile that has a base diameter of approximately 122 feet?