12. Let X be a random random variable with PMF given by: 0.7 if x = -2 0.15 ifx = 0 p(x) = 0.05 if x = 1 0.1 if x = 5 Find var(X - 2). (a) 2.1512 (b) 0.85 (c) 15.6 (d) -2.85 (e) 4.6275 3. Find E(X2) where X is a random variable with PMF given by the following table x px (x) 0.2 0 0.1 1 0.7