Let X be a random variable with the following probability distribution. Value x of X P(X-x) 0 0.05 10 0.40 20 0.45 30 0.10 Complete the following. (If necessary, consult a list of formulas.) (a) Find the expectation E (X) of X. E(X) = X 5 ? (b) Find the variance Var(X) of X. Var(x) =