Portfolio return and standard deviation Jamie Won

g is thinking of building an investment portfolio containing two exchange traded funds $($ETFs$).$ Jamie plans to invest $$6,500$ in Vanguard S&P $500$ ETF $($VOO$)$ and $$3,500$ in Invesco QQQ Trust $($QQQ$).$ Jamie has decided to analyze some historical returns to get a sense for her portfolio's possible future risk and return. Six years of historical annual returns for each ETF are shown in the following table:

a$.$ Calculate the portfolio return, $r_p,$ for each of the $6$ years assuming that $65\%$ is invested in VOO and $35\%$ is invested in QQQ$.$

b$.$ Calculate the average annual return for each ETF and the portfolio over the six$-$year period.

c$.$ Calculate the standard deviation of annual returns for each ETF and the portfolio. How does the portfolio standard deviation compare to the standard deviations of the individual ETFs?