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 Large- Company US Treasury bills stocks 123456 3.98% 6.62% 14.17 4.44 19.31 4.31 -14.37 7.33 -31.86 5.36 6 37.02 6.23 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.) a. Large-company stocks % a. T-bills % b. Large-company stocks % b. T-bills % c-1. Average risk premium % c-2. Standard deviation %