Final answer:
A white light placed over the fore and aft centerline of a vessel, showing an unbroken light over an arc of the horizon of 225 degrees and fixed to show the light from right ahead to 22.5 degrees abaft the beam on either side of the vessel, is used for navigation and signaling purposes.
Step-by-step explanation:
A white light placed over the fore and aft centerline of a vessel, showing an unbroken light over an arc of the horizon of 225 degrees and fixed to show the light from right ahead to 22.5 degrees abaft the beam on either side of the vessel, is used for navigation and signaling purposes. This type of light is commonly referred to as a masthead light or a white all-round light. It helps other vessels determine the heading and position of the vessel at night or in low visibility conditions.