How did you get on with the flashing light question?
You were looking at an isolated danger mark, typically used to mark hazards such as underwater shoal, pinnacle or rocks around which there is navigable water.
| Isolated Danger Mark | Description |
| Colour | Black with one or more broad red horizontal bands |
| Shape of buoy | Pillar or spar preferred otherwise optional but not conflicting with lateral marks |
| Top mark (if any) | 2 black spheres one above the other |
| Light (when fitted) | White |
| Rhythm | Group flashing (2) |
You are going to check the chart and your passage plan - is it expected?
You are going to give it a wide berth - if that means altering course - a good all-round check, then alter course to keep clear.
If you managed to get all that - well done.
For those of you with aspirations towards Coastal or Yachtmaster theory, try and get into the habit of doing buoy descriptions like this. It will prevent you from missing something out.