QuestionSuppose X1,X2,X3,X4X_1,X_2,X_3,X_4 are i.i.d. Bernoulli(2/3)(2/3). Define Y=2X1+3X2+4X3+5X4Y=2X_1+3X_2+4X_3+5X_4. Find Var(Y)\mathrm{Var}(Y).