A white masthead light shows through an arc of how many degrees?

The correct answer indicates that a white masthead light shows through an arc of 225 degrees. This is a standard requirement for vessels under the International Regulations for Preventing Collisions at Sea (COLREGs) and helps define the visibility and range of the masthead light.

The masthead light is typically positioned at the highest point of a vessel and is designed to be seen from a distance by other vessels. It primarily serves to indicate the presence of the vessel to those approaching from the front or sides, with the 225-degree arc ensuring visibility for vessels approaching from either side and in front.

Typically, the light is visible from directly in front (which is 22.5 degrees above the centerline) to an angle of 112.5 degrees on either side of the centerline, totaling 225 degrees. This positioning allows for clear signaling of the vessel's orientation and extent, ensuring safe navigation and avoiding potential collisions.

Understanding the specific light requirements, including their angles of visibility, is essential for maintaining safety on the water and complying with maritime regulations. The other options suggest different degrees that do not align with the standard requirements for masthead lights, making them incorrect in this context.