Question 3. (15 points) Use the following data in order to calculate the mean (average return), variance, standard deviation, and the Sharpe ratio for the following portfolio. Your portfolio includes 50% stock, 30% bonds, and 20% Treasury bills. Investment Stock Bonds Treasury bills Expected Return 8% 4.5% 2.5% Correlation between stock and bonds is 0.65 Correlation between stock and Treasury bill is 0.35 Correlation between bonds and Treasury bill is 0.25 Standard Deviation 21% 12% 0