Assume these are the stock market and Treasury bill returns for a 5-year period: Year 2013 2014 2015 2016 2017 Stock Market T-Bill Return Return () 31.7 0.02 10.9 @.02 -1.6 0.02 13.0 0.20 21.3 0.80 Required: a. What was the risk premium on common stock in each year? (Negative values should be entered with a negative sign.) 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.) Complete this question by entering your answers in the tabs below. Required A Required B Required C What was the risk premium on common stock in each year? (Do not round intermediate calculations. Enter your answers as'a percent rounded to 2 decimal places.) Risk Premium Year 2013 2014 2015 2016 2017 Required A Required B >