n the last 20 years, the average return on stock is 9.27% and the standard deviation is 18.32%. The average return on 10-year treasury note is 5.70% and the standard deviation is 8.82%. The correlation between stock and bond return is -0.5926.

1.What is the standard deviation of a 50% stock 50% bond portfolio?

2.Based on (1), In this period, the average risk-free rate is 2.14%. What is the Sharpe ratio of the 50% stock 50% bond portfolio?