It depends on which war you're referring to. I feel that the answer you're looking for is the radio, though.
One of the advantages was that the old mom & pop stores were no longer practical, because the corporations were more convenient. You didn't have to ride around to go to seven stores anymore, you would just go to the big-block store and get everything you needed there. Furthermore, corporations provided a large amount of unskilled jobs - previously, the largest part of the "American dream" was to go and start your own business, farm, etc., but now you could go get a job at a factory or supermarket, so the job market was diversified. Those are just two, but I'm sure you can think of more!
I don’t understand this language,but I need points really badly.Sorry.
The correct option is C<span>
</span><span>Swift running rivers provided the power for the factories
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</span><span>Factory Machines were running on water as they were installed on mills. in addition the soil in the North was unsuitable for agriculture. More also, the North was easily accessible by ocean for shipping of goods.</span>