🔍 Key Concepts

• Fathom curves and what they represent on nautical charts • How different depth contours (e.g., 1-, 2-, 3-fathom) are distinguished by line style in Chart No. 1 • The difference between solid, dashed, and dotted line patterns on charts

💭 Think About

• Look up the section in Chart No. 1 that explains depth contours and compare how the 2-fathom curve is drawn versus deeper depth curves. • Ask yourself: does a very shallow contour (like 2 fathoms) tend to be shown with a more noticeable or a less noticeable line pattern? • Compare which of the answer choices most closely matches the typical contour-line style used for shallow water limits around shoals and banks.

✅ Before You Answer

• Verify in U.S. Chart No. 1 under the "Depths" section how the 2-fathom curve is specifically shown. • Check whether the 2-fathom curve symbol uses solid segments, dashed segments, or dots, and in what sequence. • Confirm that you are not confusing the symbol for a fathom curve with symbols for other features like limits, cables, or area boundaries.