Assume these are the stock market and Treasury bill returns for a 5-year period:

Year		Stock Market Return (%)			T-Bill Return (%)
2013			34.20			0.14
2014			13.90			0.14
2015			3.80			0.14
2016			14.80			0.09
2017			24.30			0.11

Required:

a. What was the risk premium on common stock in each year?

b. What was the average risk premium?

c. What was the standard deviation of the risk premium? (Ignore that the estimation is from a sample of data.)