Suppose that 3 balls are randomly selected from an urn containing 3 red, 4 white, and 5 blue balls. Let X and Y denote, respectively, the number of red and white balls chosen. (a) Find the distribution of (X, Y ), i. e. find the joint probability mass function of X and Y . (b) Are X and Y independent? [Hint: To show that X and Y are not independent, it is sufficient to find a single pair of numbers x and y such that P(X = x, Y = y) 6= P(X = x, Y = y).]