A trust officer at Charles Schwizer National Bank needs to determine how to invest $100,000 in the following collection of bonds to maximize the annual return. Annual Bond Return % Maturity Risk Tax-Free?

Annual

Bond Return(%) Maturity Risk Tax Free

A 9.5 Long High Yes

B 8.0 Short Low Yes

C 9.0 Long Low No

D 9.0 Long High Yes

E 9.0 Short High No

The officer wants to invest at least 50% of the money in short-term bonds and no more than 50% in high-risk bonds. At least 30% of the money should go into tax-free investments and at least 40% of the total annual return should be tax free. Write a linear optimization model for this problem and solve it in Excel.