Answer ? also it's a two answer question.

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 is an example of a concurrent power? a. when a group of states work together to regulate interstate commerceb. when a federal law enforcement agency state policec. when a state creates a treaty with a foreign governmentd. when a local government collects taxes on imports

What did truman suggest to stalin at the potsdam conference regarding reparations from germany