answer all three please

You've observed the following returns on Crash-n-Burn Computer's stock over the past five years: 4 percent. -8 percent, 24 percent, 19 percent, and 17 percent. What was the arithmetic average return on the company's stock over this five-year period? Average return What was the variance of the company's returns over this period? Variance What was the standard deviation of the company's returns over this period? Standard deviation