The interpretations of historians stay about the same.

How was rockefeller able to build his monopoly across the oil industry? he found newer and cheaper ways to refine oil, increasing his profits. he confined his business to ohio so he could buy all the refineries there. he bought up oil refineries, cut costs, and reinvested his profits in other refineries. he began to sell kerosene as well as oil, expanding his market.

Which of the following descriptions is an example of the curtual diffusion

The 15th amendment to the u. s. constitution, ratified in 1870, deals with what issue? a. prohibition of alcohol b. voting c. declaring war d. free speech