Answer:
The Appalachian Mountains
Explanation:
The Appalachian Mountains formed a natural boundary to the west. The geography and climate of the thirteen colonies separated them into three different regions: New England, the Middle Colonies, and the Southern Colonies. New England Coast Rocky coasts are common in New England.
<span>The main impact of the completion of the Panama Canal was to increased world trade.</span>
To promote the informal use of consumer credit.