Question

A and B are competing companies. An investor decides whether to buy 100 shares of A, 100 shares of B, or 50 shares of each.
A profit made on 1 share of A is a random variable X with the distribution P(X=2)=P(X=-2)=0.5.
A profit made on 1 share of B is a random variable Y with the distribution P(Y=4)=0.2, P(Y=-1)=.08.
If X and Y are independent, compute the expected value and variance of the total profit for strategies a,b, and c.