5. The opportunity cost of shifting production choices The following graph shows the production possibilities curve (PPC) of an economy that produces food and steel. The black points (plus symbols) represent three possible output levels in a given month. You can click on the points to see their exact coordinates. (?) 32 28 PPC 24 20 16 STEEL (Millions of tons 12 100 200 300 400 500 600 7 800 FOOD (Millions of pounds) Suppose the economy initially produces 300 million pounds of food and 20 million tons of steel, which is represented by point A. The opportunity cost of producing an additional 100 million pounds of food (that is, producing at point B rather than at point A) is tons of steel. Suppose, instead, that the economy currently produces 400 million pounds of food and 16.8 million tons of steel, which is represented by point B. Now the opportunity cost of producing an additional 100 million pounds of food (that is, producing at point C rather than at point B) is tons of steel. Comparing your answers in the previous questions suggests that the opportunity cost of producing 100 million additional pounds of food at point B is the opportunity cost of producing 100 million additional pounds of food at point A. This reflects the