If you freely combine the market portfolio $($Sharpe ratio $S_m=0\mathrm{.}6$ and information ratio $I_m=0)$ with the managed portfolio $($Sharpe ratio $S_p=0\mathrm{.}7$ and information ratio $I_p=0\mathrm{.}5)$ to form a risky portfolio, what is the highest Sharpe ratio that you can achieve?

$0\mathrm{.}86$

$0\mathrm{.}65$

$0\mathrm{.}92$

$0\mathrm{.}78$