Final answer:
Safe speed under Navigation Rule 6 refers to the maximum speed a vessel can travel without endangering others. It depends on factors such as visibility, traffic density, and maneuverability.
Step-by-step explanation:
The definition of safe speed under Navigation Rule 6 covers the maximum speed at which a vessel can travel without creating danger to other vessels, structures, or persons. It takes into consideration factors such as visibility, traffic density, and maneuverability of the vessel. For example, if a vessel is navigating in an area with poor visibility or heavy traffic, it should reduce its speed to a safe level to avoid potential collisions.
Keywords: safe speed, Navigation Rule 6, visibility, traffic density, maneuverability