3. (30 points) Consider two sets of measurements to determine the unknown 3: X1 =s+n, X2=s+n+w, where 35,11,111 are independent zero-mean random variables with variances Var(s) = of, Var(n) = 0:,Var(w) = of\" a. Determine the best linear minimum mean square error (MMSE) estimator for 3 based on X]. Compute the minimum mean square error of. b. Determine the best linear mean square error (MMSE) estimator for 3 based on both X1 and X2. Compute the minium mean square error 0%. c. Between (a) and (b) above, which estimator is superior? Justify your answer by comparing or? and 0%