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

the answer is A.

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Explanation:

i do not know if this question has options, but a main impact of the federal reserve act of 1913, which created the federal reserve bank, was the international use of the u.s. dollar, which soon became the world's leading currency - particularly during world war i, since many nations around the world asked the united states for money.

hey i did something like that before, what is the quesiton?