Stock A has a standard deviation of 15 percent per year and stock B has a standard deviation of 21 percent per year. The correlation between stock A and stock B is .30. You have a portfolio of these two stocks wherein stock B has a portfolio weight of 60 percent. What is your portfolio standard deviation? A. 14.87 percent B. 15.50 percent C. 16.91 percent D. 17.45 percent E. 18.03 percent Please show all calculations.