What was the main reason the United States and the Soviet Union became superpowers after World War II?
-> Both had nuclear weapons that the rest of the world feared.
The use of labor-saving devices in industry and agriculture. So b is the correct answer
I believe it is the Sumerian.
Agriculture was the main factor
<span>Instead, in 1857, in the case of Dred Scott v. Sanford, the United States Supreme Court declared that all blacks — regardless of whether they were slaves or free men — were not and could never become citizens of the United States. The court also ruled that the 1820 Missouri Compromise was unconstitutional.</span><span>Dec 13, 2010</span>
