Because the United States acquired the land from France as part of the Louisiana Purchase in 1803.
It's B. The Columbian Exchange is just that, the exchange of goods, plants, people, etc. between Europe and the Americas
(B) A fort was established and many were killed by disease.
After Lewis and Clark's expedition, the people of mandan village were faced by a devastating outbreak of smallpox disease in the year 1837, as much as the epidemic was devastating it played an important role in uniting the surviving people in Mandan and Hidatsa village who later interacted in trade farming and hunting
Hope this helps
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Politically: Lincoln tried preserving the Union, so the South decided to secede and this led to war.
• The most unfortunate political consequence of the Civil War was Abraham Lincoln's death.
- Lincoln also issued the Emancipation Proclamation. It went into effect on January 1, 1863, and declared, "that all persons held as slaves" in states that rebelled "are, and henceforward shall be free." the proclamation changed the focus of the war
Economic consequences:
- , the Southern economy was in ruins. Much of the war had been fought in the South
- foreign nations that once bought Southern cotton began to produce their own. As a result, post-war cotton prices plunged dramatically
- Just like in the South, a large percentage of Union soldiers went home with injuries that prevented them from working
- Buildings, railroad lines, and family farms destroyed in the war needed to be rebuilt. The nation as a whole needed to be reconstructed
Social consequences:
- The Civil War allowed African Americans to make progress in society.
- Following the Emancipation Proclamation, many free African Americans joined the Union army
- The population was reduced as a result of war casualties. Farms and homes had been destroyed.