Final answer:
A double solid yellow line prohibits passing on both sides of the centerline in traffic, aiding in safety and traffic control, especially in areas where overtaking is dangerous.
Step-by-step explanation:
A double solid yellow line prohibits traffic from passing on both sides of the centerline. In traffic management, such lines are used to control the flow of traffic and enhance safety. Where these lines are present, vehicles are not permitted to cross over to pass others, as it indicates an area where passing would be hazardous. Traffic signals are sometimes used in conjunction with road markings to further regulate speed and ensure orderly movement of traffic. For example, a red blinker signals to traffic entering an intersection to stop, while a yellow signal advises caution. At intersections where many vehicles speed through without regard for the posted speed limit, installing a traffic signal can be very effective in making vehicles slow down and preventing them from speeding through.