<span>Automobiles were luxury items owned by a few until the idea of interchangeable parts came along which helped with the formation of an assembly line. This made making cars faster, which means there were more of them and were easier for less rich people to get.
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The answer is D
Reason being that the sinking of ships by German U-boats, and a German attempt in the Zimmermann Note to get Mexico to declare war on the U.S. pushed the U.S. to getting involved.
Because of hitler mostly but hitler did not make the holacaust alone
Explanation:
It is important to notice it because use countries can help stop it.
It added fresh troops to the war that hadn't been worn Dow yet and added a new force that had near unlimited resources