am farms a 400-acre farm. Two hundred acres of the land are particularly rich in a nutrient that is favorable to growing corn but has no benefits for wheat. Sam can grow 30 bushels of corn or 25 bushels of wheat on each of these special acres. The other 200 acres are not rich in the nutrient, so Sam can grow only 10 bushels of corn or the same 25 bushels of wheat per acre. When a production possibilities frontier is bowed out, away from the origin, the opportunity cost of a good?