Exercise 4.1 of Gut (1st ed, Page 75): (a) If X ~ ber(p), show ox(t) = q + pet (b) If X ~ bin(n, p), show ox(t) = (q + pelt)" (c) If X ~ geo(p), show ox(t) = p/(1 - qet) (d) If X ~ pois(m), show ox(t) = exp{m(el - 1)}