Let X1,X2 be a random sample from a random variable X with E(X) = ,u, and V(X) = 02. a) Show that for any A, ft; = AXI + (1 MXQ is an unbiased estimator for a. b) Which of these unbiased estimators is the most accurate? i.e. for what value of A does fr; have the least variance? For full credit you must show all of your work