Which constitutional amendment best describes the relationship between the federal government and states?

Tenth Amendment

Explanation:

The tenth constitutional amendment describes the relationship between the federal government and the state government. It describes the powers not delegated to the federal government are otherwise reserved for the states. This amendment in the constitution divides powers and delegation of powers between the federal government and the state.

answer; by working independently, the states have a high likelihood of developing innovative solutions that can be employed in other states;

the density would be a smaller number.