Problem 12-8 Risk Premiums (LO2, 3] Suppose we have the following returns for large-company stocks and Treasury bills over a six-year period: Year US Treasury bills NMO 2 3 4 5 Large- Company stocks 3.96% 14.46 19.15 -14.53 -32.02 37.41 6.56% 4.40 4.27 7.31 5.20 6.37 a. Calculate the arithmetic average returns for large-company stocks and T-bills over this period. (Do not round intermediate calculations and enter your answers as a percent rounded to 2 decimal places, e.g., 32.16.) b. Calculate the standard deviation of the returns for large-company stocks and T-bills over this period. (Do not round intermediate calculations and enter your answers as a percent rounded to 2 decimal places, e.g., 32.16.) C-1. Calculate the observed risk premium in each year for the large-company stocks versus the T-bills. What was the average risk premium over this period? (A negative answer should be indicated by a minus sign. Do not round intermediate calculations and enter your answer as a percent rounded to 2 decimal places, e.g., 32.16.) C-2. Calculate the observed risk premium in each year for the large-company stocks versus the T-bills. What was the standard deviation of the risk premium over this period? (Do not round intermediate calculations and enter your answer as a percent rounded to 2 decimal places, e.g., 32.16.)