We study history by Era because

An era is a span of time defined for the purposes of chronology or historiography, as in the regional eras in the history of a given monarchy, a calendar era used for a given calendar, or the geological eras defined for the history of Earth. We study history by era to make it easy to divide periods in the past.

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please mark it the brainliest!

the influence of daoism, buddhism, and legalism on chinese culture. unlike confucianism, daoism looked to nature rather than human beings as the source of morality. according to laozi, human society has to conform to the dao (the way), or the essential unifying element of all that is. some interpret dao as nature.

answer-the island had airfields that the u.s. military needed.