Which of the following is a true statement about columbus' beliefs about the world? a. he believed the world was flat. b. he believed that the world was much larger than it actually is. c. he believed that most of the earth was covered by water. d. he believed that the earth was much smaller than it actually is.

the answer is "by providing data about careers and annual mean wages"

explanation:

the addition to geographic boundaries that might have  kept the people of the huang river civilization from traveling to far distance region is that they had learned about the other river valley civilizations but feared contact would bring invasion.

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