Fly Phoenix, a chain of self-service gas stations, must determine how to blend its hybrid petroleum products gasohol and petrolmeth. Both products are blended from 90-octane unleaded gasoline. Ethyl alcohol an ingredient of gasohol cannot exceed 10% of the final products volume. Petrolmeth may contain both ethyl and methyl alcohols, but these combined ingredients must not exceed 30% of the final products volume. The octane ratings are 120 for ethyl alcohol and 110 for methyl alcohol. Final product octane ratings must equal the average octane ratings for the ingredients by volume. Gasohol must have an octane rating of at least 91, and petrolmeth must have a rating at least of 93. There are 20,000 gallons of gasoline presently available for blending, at a cost of $1.00 per gallon. Up to 5,000 gallons of methyl alcohol can be acquired for $0.50 per gallon, and 3,000 gallons of ethyl alcohol are available at $1.50 per gallon. The demands are at least 10,000 gallons of gasohol and 5,000 gallons of petrolmeth. Fly Phoenix must meet all of the above requirements at minimum cost. Formulate this problem as a linear program.