Calculating average return, variance, and standard deviation.

You've observed the following returns on Crash-n-Burn Computer's stock over the past five years: 15 percent, -15 percent, 17 percent, 27 percent, and 10 percent. What was the arithmetic average return on Crash-n-Burn's stock over this five-year period? (Do not round intermediate calculations. Enter your answer as a percent rounded to 1 decimal place, e.g., 32.1.) Average return % What was the variance of Crash-n-Burn's returns over this period? (Do not round intermediate calculations and round your answer to 5 decimal places, e.g., 32.16161.) Variance What was the standard deviation of Crash-n-Burn's returns over this period? (Do not round intermediate calculations. Enter your answer as a percent rounded to 2 decimal places, e.g., 32.16.) Standard deviation %