What effects did the arrival of europeans have on the native peoples of the americas?

What event brought the us into wwii? what conflicts happened after the us entered the war? i know the first part of this question, i need with the second part.

What was the most important consequence of the large-scale ecological changes in africa two hundred thousand years ago?

What happened during the victorian age? a. all social classes lived near each other b. the middle class became much larger c. city populations began to decrease d. families continued to go to work together