• 1 ton of wheat is 0.5 bottles of wine (50 bottles of wine / 100 tons of wheat).

• Country A's opportunity cost of producing 1 bottle of wine is 2 tons of wheat (100 tons of wheat / 50 bottles of wine).
• 1 ton of wheat is 0.5 bottles of wine (50 bottles of wine / 100 tons of wheat).

• Country A's opportunity cost of producing 1 bottle of wine is 2 tons of wheat (100 tons of wheat / 50 bottles of wine).
• 1 ton of wheat is 0.5 bottles of wine (50 bottles of wine / 100 tons of wheat).

• Country A's opportunity cost of producing 1 bottle of wine is 2 tons of wheat (100 tons of wheat / 50 bottles of wine).

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