Suppose we have the following Treasury bill returns and inflation rates over an eight year period: Year Treasury Bills Inflation 1 7.70 9.20 2 8.46 12.88 3 6.31 7.41 4 5.48 5.24 5 5.89 7.17 6 8.11 9.52 7 11.10 13.84 8 12.70 13.19 a. Calculate the average return for Treasury bills and the average annual inflation rate (consumer price index) for this period. (Do not round intermediate calculations. Enter your answers as a percent rounded to 2 decimal places (e.g., 32.16).) Treasury bills % Inflation % b. Calculate the standard deviation of Treasury bill returns and inflation over this period. (Do not round intermediate calculations. Enter your answers as a percent rounded to 2 decimal places (e.g., 32.16).) Treasury bills % Inflation % c. What was the average real return for Treasury bills over this period? (Negative amount should be indicated by a minus sign. Do not round intermediate calculations. Enter your answer as a percent rounded to 2 decimal places (e.g., 32.16).)