In the early and mid-1800s, much of the North’s economy depended on

In the early and mid-1800s, much of the North's economy depended on unskilled labor which was supplied by immigrants from other countries.

roosevelt believed that in light of the country's recent military successes, it was unnecessary to use force to achieve foreign policy goals, so long as the military could threaten force. this belief, and his strategy of “speaking softly and carrying a big stick,” shaped much of roosevelt's foreign policy.

that would be the steamboat because none of the other things are forms of transportation