Which of the following is true if XXX and YYY are independent random variables?
E[X+Y]=E[X]⋅E[Y]E[X+Y] = E[X] \cdot E[Y]E[X+Y]=E[X]⋅E[Y]
Var(X+Y)=Var(X)+Var(Y)Var(X+Y) = Var(X) + Var(Y)Var(X+Y)=Var(X)+Var(Y)
Var(X+Y)=Var(X)−Var(Y)Var(X+Y) = Var(X) - Var(Y)Var(X+Y)=Var(X)−Var(Y)
E[XY]=E[X]+E[Y]E[XY] = E[X] + E[Y]E[XY]=E[X]+E[Y]