Which geographic feature limited the expansion of civilization in north africa? sahara desert congo river basin serengeti nile river

What was one major advantage that the united states industrialize rapidly in the early 19th century?

Between 1870 and 1916, approximately how many immigrants came to the united states? 10 million 25 million 75 million 125 million

Explain why american modernist writers might have perceived the world as chaotic in the early part of the 20th century. should be at least 250 words.