2. (Bonus: 10 points) In the usual random effects model for CRD: i = 1, 2 . ..a yij = H+ TitEij j = 1, 2, ...ni iid Eij ~ N(0, 02 ) Ti~ N(0, 0? ) {ri} and {eij } independent Calculate the mean, variance and distribution of the grand sample mean y.. . You may use any result from the lectures. Hint: You may need the covariances Cov(yij, (ks). Then simplify your findings in the case of a balanced design