What event finally caused the united states to enter world war i?

Which region was almost every country colonized by an imperial power in the 19th century

How did the northern u.s. change during the 19th century? select the best choice from the answers provided. a. it became more industrial. b. it became more agrarian. c. it became less populated. d. it became less diverse

Which empire was called "the sick man of europe? "