This would be C. 1830- Baltimore and Ohio Railroad :)
The Panama Canal was built to connect the Atlantic Ocean, and the Pacific Ocean.
Hope this helped! c:
During the Civil War, it was much easier for the North to obtain and manufacture items that were needed. Certain items during this time were very crucial and important for war, like weapons, clothes, medical supplies, and other things that were needed in abundance. The North definitely had an advantage during this time, as they had larger cities which contained industries which made much needed items.
Gunpowder was obviously needed during this time, but its ingredients had to be imported. Since the North controlled the main ports, they would get much more gunpowder and even some other items from outside forces.