In the early 1800s, which major North American river were many American settlers using for trade?

Missouri River

Explanation:

The importance of the river for transportation and trade greatly increased in the early 1800s as paddle wheeled steamboats became popular. Cities along the Mississippi such as St. Louis boomed. During the Civil War, both the North and the South used the river for transportation.

the answer is: c. c.it limited the president’s power to start wars.

the war powers resolution of 1973 requires the president to notify the congress whenever the president wanted to order a military operation to other countries within 48 hours. if after being reviewed the congress disagree with the proposal, that the president will be banned from ordering the operation.