Final answer:
Early factories were built near rivers because they provided transportation and power for the factories.
Step-by-step explanation:
Early factories were generally built near rivers because they provided transportation for goods and raw materials and powered the factories. Rivers were a crucial source of power in the early industrial period, as waterwheels could be used to generate energy for machinery. Moreover, rivers allowed for the transportation of goods and raw materials to and from the factories, making it easier and more cost-effective. This helped in the growth of the factory system and the industrialization of societies.
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