🔍 Key Concepts

• U.S. Aids to Navigation System (Inland) – especially shapes and colors of daymarks on the Western Rivers • How light structures (like Parker Landing Light) are often combined with dayboards/daymarks that mark the channel edge • Relationship between odd/even numbers and green/red aids on the Western Rivers

💭 Think About

• On the Western Rivers, when you are moving upbound (against the current), which side of the river are green aids on, and what shape usually marks that side? • Consider what type of aid Parker Landing Light is likely to be (channel edge vs. special mark) and which standard daymark shape would be paired with that color for that function. • Look at the answer choices: only one matches the standard IALA B / U.S. ATON pattern for a normal green lateral daymark.

✅ Before You Answer

• Confirm from your study materials how green lateral daymarks are shown: is the shape normally a square or a triangle? • Verify whether red/green rectangles or green diamonds are used for ordinary lateral marks, or if they are used for other types of markings (like junctions or special-purpose marks). • Check the Western Rivers System convention for shapes on the left and right banks when proceeding upstream and match that to a green daymark.