Consider the following table for a period of six years: Year N Returns Large- U.S. Company Treasury Bills Stocks - 15.09% 7.37% -26.59 8.03 37.31 5.95 24.01 5.47 7.32 5.49 6.65 776 incs a-1. Calculate the arithmetic average returns for large-company stocks and T-bills over this time period. (Do not round intermediate calculations and enter your answers as a percent rounded to 2 decimal places, e.g., 32.16.) a-2. Calculate the standard deviation of the returns for large-company stocks and T-bills over this time period. (Do not round intermediate calculations and enter your answers as a percent rounded to 2 decimal places, e.g., 32.16.) Large-company stocks T-bills a-1. Arithmetic average return a-2. Standard deviation Calculate the observed risk premium in each year for the large-company stocks versus the T-bills. b-1. What was the arithmetic 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.) b-2. 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.) b-1. Average risk premium b-2. Risk premium standard deviation