#4.1 (20 points) Let X1, X2, , X\" be a random sample from the given statistical model. Check if the following estimators are unbiased for the given parameter function (309) of 9 . A. For normal distribution N(,u, 0'2) with known pi and 0 = 0'2 , 915(6) = 0'4 and two estimators are nl n 2 T100 2 S4 and T200 2 2(Xi \")2] . '=1 n + 1 2n + n2 , B. For Bernoulli model with parameter 9 . 915(9) = 9(1 t9) and two estimators are T1(X)= :1) EX,- nanXl-J . andT2(X)=X(lX) . i=1 n(n i=1