Australia can produce 50 barrels of ethanol or 30 tonnes of wheat a day, while the United States can produce 120 barrels of ethanol or 20 tonnes of wheat a day.
Initially, both Australia and the US spent half a day producing ethanol and half a day producing wheat. However, they now decide to specialise in producing the product that they have a comparative advantage and trade their products in the world market. What are the total gains from trade?

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