Consider the following rates of return: a. Calculate the arithmetic average returns for large-company stocks and T-bills over this period. b. Calculate the standard deviation of the returns for large-company stocks and T-bills over this period. 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? 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