Answer:
1.In 1917 the use of unrestricted German submarine warfare caused the U.S. to enter the war on the side of the Allies. How did Germany's use of unrestricted submarines warfare bring the United States into WWI ? A German U-boat had sunk the British passenger ship the Lusitania at great loss of life.
2.World war 1 leads to suffer the Americans people a lot . Young men were forced to go for war which leads to the deplete the financial condition of the house hold. Industry starts to suffer a lot as most of the people who were working has to go for war and man power decreases.
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Explanation: