was The Erie Canal was one reason that manufacturers had to increase the prices of goods being shipped to the Midwest.

No, it wasn't. Instead because of the Erie Canal, prices of goods dropped.

Explanation:

The Erie Canal construction was completed on October 25, 1825. With this development,it allowed for  New York City  to gain direct access to the  regions of the Midwest which contributed to the boost in the economy as the canal encouraged  the transport of goods to the midland reducing cost of transportation to about a tenth of its initial prices thereby causing a decrease in the price of goods.

4 copper and gold, the california gold rush is why im pretty sure.