Which of the following actions is required before crossing railroad tracks?

When approaching railroad tracks, it's crucial to stop no closer than 15 feet and no further than 50 feet from the nearest track. This distance is important for several reasons. First, it provides you with a safe buffer zone, allowing you to see if a train is approaching without being in a position that could put your vehicle in danger should a train appear. Additionally, stopping within this range allows enough time to assess the situation, ensuring that it is safe to proceed before crossing.

Stopping closer than 15 feet may not give you an adequate view of the tracks, while stopping beyond 50 feet could mean you're too far from the track to clearly see or hear an approaching train. Thus, adhering to this specific stopping distance is a safety measure aimed at preventing accidents at railroad crossings.