[HELP]
What were 2 contributions of African Americans during the war?

What is zinn's approach to the study of history? what does he suggest occurs when history is told is the story of human progress?

Indicate the point where a monopoly will set its price

The telegraph, the transatlantic telegraph cable, and the telephone were important to businesses after 1850 because of a. they created a system for developing new inventions. b. they filled a need that other inventions of the day could not. c. they attracted investors and created the stock market. d. they made picture-taking a popular american pastime.