Kelly decided to accept the risk and purchased a high growth stock. Her returns for the past five years are 32 percent, 24 percent, -48 percent, 12 percent, and -9 percent, respectively. What is the standard deviation of these returns? Select one: a. 23.20 percent b. 35.46 percent c. 17.88 percent d. 32.03 percent e. 28.39 percent