During World War II, unemployment in the U. S. declined and the gross national product increased because :

America's involvement in World War II had a significant impact on the economy and workforce of the United States. The United States was still recovering from the impact of the Great Depression and the unemployment rate was hovering around 25%. Our involvement in the war soon changed that rate.

Explanation: Many Americans feared that the end of World War II and the subsequent drop in military spending might bring back the hard times of the Great Depression.

c.) the country needed a stronger central government.

a plantation economy is an economy based on agricultural mass production, usually of a few commodity crops grown on large farms called plantations. plantation economies rely on the export of cash crops as a source of income.

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