Which of the following is true about the emergency signaling mirror?

The emergency signaling mirror can indeed signal up to 10 miles under optimal conditions, making it an effective signaling device in emergency situations. This distance is significant because it allows individuals to communicate their location to rescuers who may be far away, increasing the likelihood of being spotted. The effectiveness relies on the ability to reflect sunlight, which enhances visibility over long distances, particularly when aimed at search aircraft or vessels.

While there are factors that can diminish its effectiveness, such as overcast weather or nighttime conditions, the mirror itself is designed for use during the day when sunlight is available. The ability to signal effectively over great distances is a critical feature that makes the mirror a valuable tool in survival kits and emergency preparedness.