Hello,

well, if you want to be complicated... any random variable is independent with any constant.

But for the first question, you just have to use the linearity of the expectation : E(aX+b)=aE(X)+b, where a and b are constants.

For the second question, Var(aX+b)=aČVar(X), because Var(constant)=0, and if you don't see why, go back to the definition of the variance.

For the last question, is it x or X ?