Need help with these 2! Thank you!

1)A stock had returns of 6 percent, -22 percent, 18percent, 12 percent, and -2 percent over the past five years. What is the standard deviation of these returns?

A) 18.74 percent

B)10.21 percent

C)11.68 percent

D)15.52 percent

E)13.49 percent

2) A stock has annual returns of 5 percent, 21 percent, -12 percent, 7 percent, and -6 percent for the past five years. The arithmetic average of these returns is _____ percent while the geometric average return for the period is _____ percent.

A)3.89; 3.52

B)3.89; 4.26

C)3.62; 3.89

D)3.00; 3.28

E)3.00; 2.37