Youve observed the following returns on Crash-n-Burn Computers stock over the past five years: 17 percent, 15 percent, 19 percent, 29 percent, and 10 percent. What was the arithmetic average return on Crash-n-Burns stock over this five-year period? What was the variance of Crash-n-Burns returns over this period? What was the standard deviation of Crash-n-Burns returns over this period?