A manufacturer produces sacks of chicken feed from two ingredients, A and B. Each sack is to contain at least 10 ounces of nutrient N1, at least 8 ounces of nutrient N2, and at least 12 ounces of nutrient N3. Each pound of ingredient A contains 2 ounces of nutrient N1, 2 ounces of nutrient N2, and 6 ounces of nutrient N3. Each pound of ingredient B contains 5 ounces of nutrient N1, 3 ounces of nutrient N2, and 4 ounces of nutrient N3. If ingredient A costs 8 cents per pound and ingredient B costs 9 cents per pound, how much of each ingredient should the manufacturer use in each sack of feed to minimize his costs?