How did the robber barons control their industries

A robber baron is a nineteenth century businessman who used any (questionable) practice to get their wealth. They The practice they used is called monopoly. Monopoly is a market situation where producer(s) controls the supply of good or service and where the entry of new producers are greatly restricted or even prevented.

Explanation:

so they can defeat there oppenent

regarding the law, the 15th amendment was specifically designed thinking in the rights of black free men.

even though ratified on february 3, 1870, the promise of the 15th amendment would not be fully applied for a long time.poll taxes and literacy tests would allow southern states disenfranchise african americans. only in 1965 the voting rights for african americans would be actually able to vote in the south.

in 1965, president johnson signed the voting rights act, which aimed to overcome legal barriers that prevented african americans from voting as it was guaranteed by the 15th amendment to the u.s. constitution.