Consider portfolio $P$ with two assets A and B

$\backslash$table$[[,$A$,$B$,\backslash$table$[[$Coefficient of$],[$correlation between C$],[$and D$]]],[$Expected Return E$($R$),20\%,15\%,-1],[\backslash$table$[[$Standard$-$Deviation$],[$SD$($R$)]],10\%,5\%,]]$

We suppose that the own wealth of the investor is $20000$

Explain why we can't choose between A and $B$

Compute the Ep and Standard deviation SD of portfolio $P1$ with $50\%$ in A and $50\%$ in $B.$

Compute the Ep and Standard deviation SD of portfolio $P2$ with $40\%$ in A and $60\%$ in $B.$

Compute the Ep and Standard deviation SD of portfolio P$3$ if the investor borrows $10000($interest rate is $12\%)$ and invest all money in B$.$

Compute the Ep and Standard deviation SD of portfolio $P4$ if the investor borrows $10000($interest rate is $12\%)$ and invest $12000$ in A and $18000$ in B$.$

What are the best portfolios and what are the worst portfolios between P$1$ P$2$ P$3$ P$4$