The tenth amendment of the u. s.
reserves to the states any powers not delegated to the national government
reserves to the national government any powers not delegated to the states
implies that certain powers are the responsibility of the national government
implies that certain powers are the responsibility of the state governments

Explanation:

The 10th Amendment puts limits on the powers of the federal government.  It reserves powers for the states (and for the people themselves) any powers not specifically designated to the federal government in the United States Constitution.   Any laws and powers exercised by the states still must be in accord with what is stated in the US Constitution, however.

For some historical context, we might also consider that the original framers of the US Constitution thoughts that statements such as the 10th Amendment -- and all of the first 10 Amendments, known as the Bill of Rights -- were already inherent in the Constitution as it was written.  They had composed a constitution that intentionally placed limits on the federal government. So, stating such a limit in an amendment seemed like a repetition of what was already apparent in the Constitution itself.  As noted by the National Constitution Center, "The Constitution’s Framers thought that a bill of rights was appropriate for an unlimited government, but not for a limited one like the national government created by the Constitution. The Constitution accordingly sought to secure liberty through enumerations of powers to the government rather than through enumerations of rights to the people."

Nevertheless, to assure those who wanted the rights of the people specifically listed and protected, Amendments 1 through 10 were added to the Constitution as a Bill of Rights to affirm those protections.

answer; no longer than a reasonable period of time;

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