We have $500$ million available. to build our portfolio. We want to invest in a mix of bonds, stocks and coverment bond up to $1$ year.

Bond class $1$ has an expected yield of $4\mathrm{.}7\%.$

Bond class $2$ has an expected yield of $6\mathrm{.}3\%.$

Bond class $3$ has an expected yield of $5\mathrm{.}8\%.$

Share class $1$ has an expected yield of $12\mathrm{.}0\%.$

Share class $2$ has an expected yield of $10\mathrm{.}9\%.$

Share class $3$ has an expected yield of $14\mathrm{.}7\%.$

Government bonds have an expected yield of $3\mathrm{.}2\%.$

We set the following conditions:

$1)$ We invest for $500,000,000$ ISK.

$2)$ We invest a minimum of $10\%$ in government bonds.

$3)$ We invest a minimum of $25\%$ in bonds in total, and a minimum of $7\mathrm{.}5\%$ in each bond class separately.

$4)$ We invest a maximum of $45\%$ in shares in total and a maximum of $20\%$ in each share class individually.

$5)$ We invest as much in bonds combined as in stocks combined.

Build a model and maximize expected returns with SIMPLEX. What will be the return on the portfolio in $\%$ and money?