Question: when a country has a comparative advantage in the production...
When a country has a comparative advantage in the production of a good, it means that it can produce this good at a lower opportunity cost than its trading partner. Then the country will specialize in the production of this good and trade it for other goods.
The following graphs show the production possibilities frontiers (PPFs) for Freedonia and Sylvania. Both countries produce grain and coffee, each initially (i.e., before specialization and trade) producing 12 million pounds of grain and 6 million pounds of coffee, as indicated by the grey stars marked with the letter A.