Final answer:
The query investigates who has the obligation to not hinder traffic separation schemes. Traffic laws and signals regulate vehicle flow, while government regulations can control the use of roads for public gatherings, with an emphasis on safety and impartiality.
Step-by-step explanation:
The question is asking about the entities that cannot impede traffic separation schemes. Traffic separation schemes are meant to organize the flow of traffic, typically on roads and highways, to ensure safety and efficiency. For example, a traffic signal installation is expected to make vehicles slow down, adhering to the posted speed limit and preventing them from speeding through intersections.
Additionally, the government has authority to regulate rallies and protests that take place on roads to ensure public safety and order, requiring permits and advance notice without discriminating based on viewpoints. The development of the federal interstate system under the Federal Highway Act focused on improving high-speed transportation across the nation, which sometimes resulted in bypassing smaller towns, affecting their economies.