It is the federal principal or system of government.
War industry was a major endeavor, massive both in terms of scale and costs involved. New technologies, munitions, weapons had to made and designed. This meant there was a need for massive number of new workers and subsequently a need for new houses where the workers would live. That was the difficulty that the industry had to face.
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Before nails were invented, carpenters,furniture makers ship builders
Answer:
B is the answer. Hope this helped.
