What section of a research paper should contain the main idea?

The nye committee report created the impression that america's entry into world war i was influenced by

How did the completion of the transcontinental railroad change the lives of american citizens? a-it increased the wealth of all americans and enabled them to travel more. b-it made cross-country travel too expensive for ordinary americans. c-it decreased the safety of americans who moved to settle the plains. d-it shortened travel time between the east and west for all americans.

Pls which of the following political figures was a strong supporter of the second bank of the united states. a. john c. calhoun. b. henry clay. c. andrew jackson. d. martin van buren.