Given below is a bivariate distribution for the random variables x and y. f(x, y) x y 0.2 50 80 0.3 30 50 0.5 40 60 (a) Compute the expected value and the variance for x and y. E(x) = E(y) = Var(x) = Var(y) = (b) Develop a probability distribution for x + y. x + y f(x + y) 130 80 100