Year 2013 2014 2015 2016 2017 Return (6) 35.60 15.10 -5.00 16.70 25.50 Return (1) 0.20 0.20 0.20 0.07 0.09 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.) Complete this question by entering your answers in the tabs below. Required A Required B Required What was the standard deviation of the risk premium? (Ignore that the estimation is from a sample of data.) (Do not rouni Intermediate calculations. Enter your answer as a percent rounded to 2 decimal places.) Standard deviation 15.05%