Solve the linear programming problems in Problems 56-59.

Your broker tells you of two investments she thinks are worthwhile. She advises that you buy a new issue of Pertec stock, which should yield \(20 \%\) over the next year, and then to balance your account she advises Campbell Municipal Bonds with a \(10 \%\) yearly yield. The bond-to-stock ratio should not be greater than 3 to 1 . If you have no more than \(\$ 100,000\) to invest and do not want to invest more than \(\$ 70,000\) in Pertec or less than \(\$ 20,000\) in bonds, how much should be invested in each to maximize your return?