Answer:
The Qin rulers united China by conquering all the warring states and ruled over them. The first Qin ruler called himself the first emperor of the unified China. During the Qin rulers' reign, their army generals conquered additional territory and so the size of China grew. The Qin rulers abolished feudalism to prevent the conquered states from becoming independent again. The whole of China was divided into administrative units, similar to states or provinces. Each administrative unit was ruled by army commanders.
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