say you perform one bernoulli experiment where outcome X = 0 and X=1 are failure and success, respectively. then you have P(X=0) = 1-p and P(X=1) = p. what if you expand this to two bernoulli experiments? only 1/4 cases would be successful, so you would have: P(X=1) = p^2 E(X) = p^2 Var(X) = ? i'm hung up on how to calculate Var(X). any thoughts?