Assume X1,X2,X3, X4,X5,X6 are i.i.d. random variables that follow some distribution with mean u and variance 02. Here we form the estimator fr : 4X1 5X 3 + 2X5 to estimate ,LL. (a) [5 points] Calculate the bias of the estimator fr. (b) [5 points] Calculate the variance of the estimator [1. (c) [5 points] Calculate the mean square error of the estimator [rt