🔍 Key Concepts

• Stability and trim diagrams often use standardized symbols for points like center of gravity, center of buoyancy, and reference lines • Look at how the vertical and horizontal elements of symbol 5 might suggest a reference line on the ship • Compare the shapes of all five symbols and think about which one would most logically indicate a line of symmetry on the vessel

💭 Think About

• Ask yourself which answer choice would reasonably be shown by a single, simple line-based symbol rather than by a more complex geometric shape • Consider where on a ship you would find the quantity in each answer choice, and whether it is usually represented as a point, a region, or a line • Think about how naval architects mark the ship’s main fore‑and‑aft reference used to measure offsets and cross‑sections

✅ Before You Answer

• Verify which of the options is normally represented as a longitudinal line running fore and aft through the vessel • Check whether any of the other symbols in the figure already suggest a volume or amount of water displaced, so you don’t confuse them • Make sure you can rule out flooding-related limits versus pure geometric reference symbols on plans and diagrams