$1.$ Calculate Arithmetic average returns for S&P and T bills over the peroid $1970-1975$

ii$)$ Calculate standard deviation of the returns for S&P and T bills

iii$)$ Calculate the observed risk premium in each year for Canadian S&P stock versus T$-$bills what was the average risk premium over this period what was the standard deviation of the risk premium over this period

iv$)$ Is it possible for the risk premium to be negative before an investment is undertaken $?$ can the premium be negative after the fact? Explain