You've collected the following historical rates of return for stocks A and B:

Year (t)	rA,t	rB,t
2016	0.02	0.04
2015	0.08	0.05
2014	0.12	0.07

What was the average annual return for stock A

What was the average annual return for stock B?

(Only Part 3 and Part 4 need answers)

Part 3

What was the standard deviation of returns for stock A?

Part 4

What was the standard deviation of returns for stock B?