Increasing feelings of nationalism among many groups led to which consequence after world war i - world history sem2 apex?

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.

Space is not completely empty. there are small particles in space. what happens when these particles come together?

Which of these were effects of mass production techniques used during 1920s