1 Total trade= GDP X GDP X 100 billion dist 1.25 Country 1 has a GDP of $70 billion, Country 2 has a GDP of $30 billion, and Country 3 has a GDP of S88 billion. Country 1 is 1,600 miles from Country 2 and 5,800 miles from Country 3. Country 2 is 5,700 miles from Country 3. a. Using the gravity model, what is the total expected trade between countries 1 and 2? Trade12: S b. What is the total expected trade between countries 2 and 3? Trade23: $ c. What is the total expected trade between countries 1 and 3? Trade13: S