All steel manufactured by Steelco must meet the following requirements: between 3.2% and 3.5% carbon;

between 1.8% and 2.5% silicon; between 0.9%

and 1.2% nickel; tensile strength of at least 45,000 pounds per square inch (psi). Steelco manufactures steel by combining two alloys. The cost and properties of each alloy are given in the file P04_69.xlsx. Assume that the tensile strength of a mixture of the two alloys can be determined by averaging the tensile strength of the alloys that are mixed together. For example, a 1 ton mixture that is 40% alloy 1 and 60% alloy 2 has a tensile strength of 0.4(42,000)
0.6(50,000).

Determine how to minimize the cost of producing a ton of steel.