Suppose that two chips are chosen without replacement from an urn consisting of 5 white and 8 red chips. For i = 1, 2, let X; be 1 if the i-th chip is white and otherwise. a) Find the joint pmf of (X1, X2). b) Find the conditional pmf of Xı given X2 = 1. c) Show that the marginal pmf of X, and X, are the same.