Calculate the expected return and variance, E[X^2]-(E[X])^2, on 100 shares of AAPL with and without a zero-interest margin loan for a 25% margin, 50% margin and 75% margin. Please compare the results for the 3 margin values. Then calculate the return on invested capital not including the margin loan. The stock can either move up 6% or down 2% with equal probability (50%). Show all work.