Answer:
3 Examples
Explanation:
1. With the usage of the Cotton Gin, slavery exploded in the South, helping the economy even further.
2. With the introduction of factories in the North, people were earning more and more money to make a living and it improved the Norths economy
3. The train made traveling out West just that much easier, and so many people carved out a living there.
I assumed you were talking about the 1800's. So sorry if this doesn't help.
