Xn) 16. Suppose X is a random variable with PMF p(x) = (0.5 if x = 1 0.5 if x = -1 Let Y = - X and let W be another random variable with the same PMF as X, but independent of X. (a) Is Y independent of X? (b) Is it true that P(X = a, W = b) = P(X = a) P(W = b) for any (a, b)? (c) Compute cov( X, Y)