9 spheres of the same size are made from melting a solid cylinder of 16 cm diameter and 12 cm height. What is the diameter of each sphere?	Pick one:
A) 4 cm B) 6 cm C) 8 cm D) 10 cm E) 12 cm

Rationale: volume of cylinder = pi * r ^ 2 * h volume of a sphere = 4 * pi * r ^ 3 / 3 9 * 4 * pi * r ^ 3 / 3 = pi * r ^ 2 * h r ^ 3 = r ^ 2 * h / 12 = 64 cm ^ 3 r = 4 cm d = 8 cm the answer is c .
Answer: C