(Note the difference between population and sample. ) 8.2 Suppose that Y1, Y2, Ys are independent drawings from a popu- lation in which the pdf of Y is f(y) = (2 + >)/16 for 0 = y = 4, with f(y) = 0 elsewhere. Let Z = (Y, + Yz + Y;)/3. Calculate E(Z) and V(Z)