The earliest occupation of most plains indians was
horse wrangling
bison hunting
agriculture
war

Bison Hunting

Explanation:

The vison resided in the plains and were hunted by such native americans

the correct answer is “opportunity cost”. opportunity cost is what a company misses out because it decided in one option over another one. in this case, the company decided to invest in building a factory so it gave up another possible benefit or profit in order to achieve success with the factory.  

trade-off is not the correct answer since it is a situation in which you accept losing something in return for benefits in other areas.

and finally, consequence is a general term used to accept what it comes when you make a decision. it can be a positive or negative consequence depending if the decision you took was the correct one.  

here are some major conflicts i found. maybe pick one and do more research on it. (cause i ain't writing 6 paragraphs)

in 1877, the nez perce war took place.

1881 - president james garfield was assassinated.

1882 - the chinese exclusion act was passed.

1883 - a decision in the civil rights cases legalized racial segregation in the united states.

1887 - the dawes act was passed.

1893 - the panic of 1893 took place. (what a creative name)

and there are probably other topics you can find if you just search up "united states timeline," or "conflicts in the 19th century for america."

then once you find a topic you like find out how it affected the people of america and what not. (sorry if this feels a bit short changed, history was and never will be one of my strong topics)