What factors led to the individual boom in the us late 1800

Immigration plus natural growth caused the U.S. population to more than double during the same period, rising from about 40 million to about 100 million. Distribution and communication. In the late 1800's, the American railway system became a nationwide transportation network.

Explanation:

b. 155 enlisted men and no officers

c. free trade can lead to low pay for workers in poorer countries.