10-11. Let {X1,X2, . . . ,Xn} constitute a set of sample random variables taken from a general population probability density function with E(Xi) = μ

 =

μ,E(X2 i ) = μ



2, and E(X4 i ) = μ



4 all finite. Verify that S2 = ni

=1

(Xi−X)2 n−1 is a consistent estimator of σ2.