Let X be a random variable with the following probability distribution. Value x of X P(X=x) 40 0.35 50 0.05 60 0.45 70 0.15 Complete the following. (If necessary, consult a list of formulas.) (a) Find the expectation E (X) of X. E(X) = 1 X ? (b) Find the variance Var(X) of X. Var(x) = 0