Idont understand why people come on here and say i think the answer if you dont have the answer why respone peoples grades are at stake we come here for straight answers

it is an infinitive phrase with a subject.

well, number 1, the 1920s was not economically prosperous until the start of the lend-lease act, which employed large amounts of people in producing equipment for the allies.

b. world war ii is your answer, because wwi had already ended at 1918, and the cold war was after 1945.

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