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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.

Full-service brokerage firms a. have lower commissions. c. provide no investment advice. b. offer portfolio management. d. teach you how to do market research.

How did the united states obtained the purchase of floridia to extand its frontiers to the pacific ocean