A. A stock produced returns of 13 percent, 22 percent, and 5 percent over three of the past four years, respectively. The arithmetic average for the past four years is 16 percent. What is the standard deviation of the stock's returns for the four-year period? Write your answer in percentage form, and round your answer to 2 decimal places. For example, put 9.29, not 0.93.

B. Alpha Industries stock had returns of 12 percent, 23 percent, and 7 percent over three of the past four years, respectively. The arithmetic average for the past four years is 24 percent. What is the standard deviation of the stock's returns? Write your answer in percentage form, and round your answer to 2 decimal places. For example, put 9.29, not 0.93.