Please note: The post contains multiple questions. The eNotes Homework Help policy allows for one question per post. This answer addresses Question 2.
The National Supremacy Clause is part of Article VI of the U.S. Constitution. Section 1, Clause 2 of that article states:
This Constitution, and the Laws of the United States which shall be made in Pursuance thereof; and all Treaties made, or which shall be made, under the Authority of the United States, shall be the supreme Law of the Land; and the Judges in every State shall be bound thereby, any Thing in the Constitution or Laws of any state to the Contrary notwithstanding.
In this clause, “national supremacy” refers to the designation as the Constitution and laws as “the supreme Law of the Land….” Its relationship to the states’ reserved powers is also considered by the statements regarding the obligation of judges to adhere to that supreme law, and regarding other states’ constitutions and laws. Although there have been many interpretations of the limits of state power, the article is clearly requires all judges—not just federally appointed ones—to “be bound” by the federal Constitution in every case they consider. Furthermore, while the article does not specify what laws a state may pass, it is equally clear in stating that the contents of an state’s constitution or law will not take precedence over federal mandates of this “supreme Law.” The framers’ intention was to guarantee national union, which would be put to the ultimate test during the Civil War.
The states’ reserved powers were specifically addressed later, in the 10th Amendment to the Constitution.
The powers not delegated to the United States by the Constitution, nor prohibited by it to the states, are reserved to the states respectively, or to the people.
The narrow wording has given rise to multiple interpretations. Because the amendment states only that the powers are either “not delegated… nor prohibited” are reserved to the states, the limits on the federal government are not precisely specified.