In this questions: Calculating Returns Refer to Table $10\mathrm{.}1$ in the text and look at the period from $1973$ through $1980.$ a$.$ Calculate the average return for Treasury bills and the average annual inflation rate $($consumer price index$)$ for this period. b$.$ Calculate the standard deviation of Treasury bill returns and inflation over this time period. c$.$ Calculate the real return for each year. What is the average real return for Treasury bills? d$.$ Many people consider Treasury bills to be risk$-$free. What does this tell you about the potential risks of Treasury bills? There are two different answers provided in chegg, one uses artihmetic average return and the other uses straight forward, answers are different. For arithmetic, it uses different set of numbers to calculcate answer $($a$).$ Example ARR for Treasury bills from $1973$ to $1980$ the other answer gives the numbers in the table whihc is $6\mathrm{.}93,8\mathrm{.}00,5\mathrm{.}80$ etc, sum them up and divided by observation which is $8$yrs$.$ The arithmetic ones give $0\mathrm{.}170\mathrm{.}10,0\mathrm{.}06,$ sum them up and divide by $8$ how are these numbers calculated?