If XXX and YYY are independent random variables with Var(X)=36\text{Var}(X) = 36Var(X)=36 and Var(Y)=64\text{Var}(Y) = 64Var(Y)=64, what are Var(X+Y)\text{Var}(X + Y)Var(X+Y) and Var(2X−Y)\text{Var}(2X - Y)Var(2X−Y)?
Var(X+Y)=100(X+Y) = 100(X+Y)=100; Var(2X−Y)=208(2X-Y) = 208(2X−Y)=208
Var(X+Y)=100(X+Y) = 100(X+Y)=100; Var(2X−Y)=172(2X-Y) = 172(2X−Y)=172
Var(X+Y)=128(X+Y) = 128(X+Y)=128; Var(2X−Y)=208(2X-Y) = 208(2X−Y)=208
Var(X+Y)=100(X+Y) = 100(X+Y)=100; Var(2X−Y)=128(2X-Y) = 128(2X−Y)=128