Answer:
1844-1877 As the nation expanded and its population grew, regional tensions, especially over slavery, led to a civil war — the course and aftermath of which transformed American society. Key Concept 5.1: The United States became more connected with the world as it pursued an expansionist foreign policy in the Western Hemisphere.
Explanation:
slavery started the Civil war. problems between the north and south
Winter bc it freezes the crops
Answer:
Settle the new territories in an orderly manner
That is true. By making travel on rivers more efficient.