^^^ Just need answers for Part B (standard deviation):

I calculated it to be 2.35% and 2.93%, however it counted me wrong...

Suppose we have the following Treasury bill returns and inflation rates over an eight-year period: Year Treasury Bills Inflation 7.45% 8.90% 8.17 6.04 5.33 5.72 7.92 10.86 12.42 12.55 7.12 5.11 6.98 9.31 13.57 12.87 6 a. Calculate the average return for Treasury bills and the average annual inflation rate for this period. (Do not round intermediate calculations and enter your answers as a percent rounded to 2 decimal places, e.g., 32.16.) Average return Treasury bills Inflation 7.99 % 9.55 % b. Calculate the standard deviation of Treasury bill returns and inflation over this period. (Do not round intermediate calculations and enter your answers as a percent rounded to 2 decimal places, e.g., 32.16.) Standard deviation Treasury bills Inflation c. What was the average real return for Treasury bills 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.) Average real return