What does a sign with black lettering on a yellow background indicate?

• It provides directional information for exits.
• It warns of potential hazards or road conditions ahead.
  Explanation:

  "Signs with black lettering on a yellow background are used to warn drivers about potential hazards, such as curves, intersections, or changes in road conditions. These signs help ensure drivers stay alert to safety risks."
• It indicates a school zone.
• It shows the speed limit for the area.