Answer:In the United States, the Constitution has established a system of “dual sovereignty,” under which the States have surrendered many of their powers to the Federal Government, but also retained some sovereignty. Examples of this dual sovereignty are described in the U.S. Constitution.
Explanation:The doctrine also was used as an argument for the theory known as nullification, which claimed that states had the right to annul an act of the federal government within their boundaries, and for the claim that the states, by virtue of their sovereignty, had the right to secede from the Union.
B.The Oregon Border, because the US claimed all of it from Britain.
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9 power treaty is...
a treaty resulting from the Washington Armaments conference. It pledged the signers to support the principle of Open Door Policy which enable all nations to compete for trade and investment opportunities in China on equal footing rather than allow individual nations to create economic monopolies in particular regions. The nine countries were: US, Britain, France, Japan, Italy, China, Belgium, Portugal, and the Netherlands
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Answer: Rivers provided both fresh water and good soil.
