Suppose we have the following returns for large-company stocks and Treasury bills over a six-year period:

Year	Large Co.	T-Bill
1	3.98%	6.62%
2	14.17%	4.44%
3	19.31%	4.31%
4	-14.37%	7.33%
5	-31.86%	5.36%
6	37.02%	6.23%

a. Calculate the arithmetic average returns for large-company stocks and T-bills over this time period.

b. Calculate the standard deviation of the returns for large-company stocks and T-bills over this time period.

c. Calculate the observed risk premium in each year for the large-company stocks versus the T-bills. What was the arithmetic average risk premium over this period?

d. Calculate the observed risk premium in each year for the large-company stocks versus the T-bills. What was the standard deviation of the risk premium over this period?