(a) Define the hypergeometric random variable and explain briefly. (10 P) (b) The components of a 6-component system are to be randomly chosen from a thousand of 20 used components. The resulting system will be functional if at least 4 of its 6 components are in working condition. If 15 of the 20 components in the bin are in working condition, what is the probability that the resulting system will be functional? (Use the hypergeometric random variable.) (15 P)