Answer:
the trade balance and the exchange rate.
Explanation:
Open-economy macroeconomic model is one that studies the open economy where the domestic economy interacts with the external (foreign) economy. It considers trade that colours with other countries and so considers trade balance and exchange rate. This is aimed at maximising satisfaction for the economy. Countries usually focus on goods they have comparative advantage producing and import goods they do not have comparative advantage in.
On the other hand a closed economy does not involve in international btrade with other countries.