The skill of dividing history into eras based on important features is called

Periodization is the process or study of categorizing the past into discrete, quantified named blocks of time. This is usually done in order to facilitate the study and analysis of history, understanding current and historical processes, and causality that might have linked those events.

monopolies  came to the united states with the colonial administration. the large-scale public works needed to make the new world hospitable to old world immigrants required large companies to carry them out. these companies were granted exclusive contracts for these works by the colonial administrators. even after the american revolution, many of these colonial holdovers still functioned due to the contracts and land

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