\fHints: 1. U N Uniform(0,1), then 111(U) ~ Exponential). 2. If X N gamma.(a, )8), then (:X N gamma(a, 0,8), (3 > 0 3. If Xi ~ gamma(a,,8),then 2:\":1 X,; N gamma(z?=l (11;, [3), where Xhi = 1, 2, 3..., n are independent random variables