Final answer:
When anchoring at night, one must display an all-around white light. It is not required to sound a horn every hour or turn bow and stern lights on, but keeping a lookout is advisable for safety.
Step-by-step explanation:
When anchoring at night, it is required by boating regulations to display an all-around white light to ensure that other vessels can see the anchored boat from any direction.
This is a safety measure to avoid collisions. While it is not necessary to sound a horn signal every hour, or have bow and stern lights on if the boat is at anchor, it is highly advisable to keep a lookout person on deck to monitor for any dangers, such as changes in weather conditions or approaching vessels.