Consider the following table for a period of six years: Returns Year Large-Company Stocks 1 2 3 4 5 6 -15.69% -26.77 37.43 24.13 -7.56 6.77 U.S. Treasury Bills 7.49% 8.09 6.07 6.07 5.55 7.94 a-1. Calculate the arithmetic average returns for large company stocks and T-bills over this time period. Note: 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. Note: Do not round intermediate calculations and enter your answers as a percent rounded to 2 decimal places, e.g., 32.16. a-1. Arithmetic average return a-2. Standard deviation Large-company stocks % % T-bills % %