Suppose that in the country of England, two goods can be produced on available agricultural land: wine and wool. Suppose that the opportunity costs of production are constant, so that the PPF is a straight line. Further, when all resources are devoted to wine production, England can produce 200 (thousand) barrels. When all resources are devoted to wool production, England can produce 400 (thousand) bushels of wool. What are the opportunity costs in England of producing a bushel of wool?