Q$3$: While doing research, you identify a stock opportunity for company YGR Inc., whose $E(r)$ and $$ are the same as YFK Inc., but it has a covariance of $-0\mathrm{.}01572$ with YSJ Inc.; should you replace stock YFK Inc. $($from Q$2)$ with YGR Inc. $($assume a $50\%$ distribution to each stock, and show all your work$)?$

Q$4$: Your colleague re$-$computes the statistics for YGR Inc., and the covariance of YSJ Inc., YGR Inc. $=0\mathrm{.}02218$; how does this impact the portfolio's standard deviation, and would your answer from Q$3$ change?

Q$5$: Compute the Sharpe Ratios $($reward$-$to$-$variability$)$ for the portfolios in Q #$\text{'}$s $2$ & $4($i$.$e$.,$ YSJ Inc. $+$ YFK Inc., and YSJ Inc. $+$ YGR Inc.$)-$ assume $90-$day Treasury bills are yielding $3\%,$ and that $30-$year long$-$term Government of Canada bonds $=5\mathrm{.}5\%.$