What important contributions did the business pioneers of the late 1800’s make american to economic life?

The important contributions that the business pioneers had made in the American in their economic life in the late 1800’s,  they were able to provide a wide economic gap between two parties in their economic life such as these were the people of who are rich and those who are poor.

world war i began in 1914, after the assassination of archduke franz ferdinand, and lasted until 1918. during the conflict, germany, austria-hungary, bulgaria and the ottoman empire (the central powers) fought against great britain, france, russia, italy, romania, japan and the united states (the allied powers). to new military technologies and the horrors of trench warfare, world war i saw unprecedented levels of carnage and destruction. by the time the war was over and the allied powers claimed victory, more than 16 million people—soldiers and civilians alike—were dead.

explanation:

the main reason that the constitution did not proclaim all men to be free and equal is because of the issue of slavery.