1. why were industrialists, such as vanderbilt, rockefeller, carnegie, and j. p. morgan characterized as robber barons and captains of industry?

Nineteenth-century robber barons included J.P. Morgan, Andrew Carnegie, Andrew W. Mellon, and John D. Rockefeller. In order to prevent single companies from developing a monopoly over an entire industry, public officials during this era put passing and enforcing strong antitrust laws high on their agenda.

Explanation:

d. migration

answer; /// i do believe that the correct answer is (a); a farming tribe that settled primarily along the mississippi and arkansas rivers;