Quantitative methods qeustion

If E() denotes the expectation of a variable, which of the following is/are TRUE? I.E(XY) = E(X)E (Y) if X and Y are independent. Il.the variance can be calculated without knowing the value of E(X) Ill.the variance of a random variable X is denoted as E(X )-(E(X)) IV.E(XY) = E(X) - E(Y) if X and Y are mutually exclusive Select one: O a. Ill & IV only O b. I only c. ll only d. | & Ill only