The printing press and paper books
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.
It extended the number of hours in the day when people could work and play.
