1. Alpha Industries stock had returns of 17 percent, -11 percent, 9 percent, and 2 percent for four of the last five years, respectively. The average return of the stock over this period was 8.7 percent. What is the standard deviation of the stock's returns?
2. Stock X has a standard deviation of 21 percent per year and stock Y has a standard deviation of 6 percent per year. The correlation between stock A and stock B is .38. You have a $13,500 portfolio of these two stocks wherein you have invested $5,670 in stock X. What is your portfolio standard deviation?