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Answer:
The Great Plains had rivers which allowed various Native American tribes to camp along these rivers while they were following the buffalo. So again, the geography of the area provided this availability of food and places to stay and feed and water their horses.
Answer:
The further the latitude away from 0, the less solar energy distribution.
Explanation:
As you get away from the latitude of zero in a northern or southern direction, the energy distribution will decrease, due to the colder climate as you go south or north.