Suppose that X,Y, and Z are jointiy distributed random variables, that is, they are defined on the same sample space. Suppose that we also have the following. E(X)=8Var(X)=4E(Y)=6Var(Y)=17E(Z)=5Var(Z)=39 Compute the values of the expressions below. E(4+Y)=E(5X+Y)=Var(4Z)+4=E(2X2)=.