(10 points) Let X be a continuous random variable with expected value E(X) : i and the Icekm if a: 2 0, exponential density function f (11:) : _ 0 otherw1se. for a constant k > 0. Hint: In class we showed [000 kme'kcdm : i. We can use this result directly when solving this question. (a) (2 points) Find 1:. (b) (4 points) Compute the variance Var(X). (c) (4 points) Let Y : #. Compute the standard deviation 0(X + Y)