Coasts and rivers. They show for better trade, and provide a means of food and transportation.
B. The Roman Empire traded with Han China because Chinese silk had been found in early Roman cities.
Since you did not mentioned the issue, the benefits of an international agreement :
- Creating a wider choices of solutions to address the issue since many countries with different resources involved in it
- Making the solutions easier to regulate since the members now binded by written agreement
To discuss their grievances with the British government.