Two construction contracts are to be randomly assigned to one or more of three firms. Numbering the firms I, II, and III, let X1 be the number of contracts assigned to firm I, and let X2 be the number assigned to firm II. (A firm may receive more than one contract.)
a). Find the joint probability distribution for X1 and X2.
b). Find the marginal distribution for X1. c). Find P(X1 = 1|X2 = 1).