🔍 Key Concepts

• Chart symbols and line styles for pipelines, cables, and dikes on U.S. river charts • The difference between how submarine pipelines and submarine cables are drawn (solid vs dashed, pattern, labels) • How river engineering structures like dikes and weirs are usually shown (alignment with shore, labels, and shapes)

💭 Think About

• Look at how other pipelines or cables are shown on the same chart: do they use the same line style as the dashed line at mile 390.5? • Consider the physical nature of each option: which of these would most likely extend across or along the river in a way that matches the location of the dashed line? • Check for nearby labels or features (like dikes, fields, structures) whose limits or centerlines might logically be marked with a dashed line.

✅ Before You Answer

• Verify the chart legend for how dashed lines are used for underwater utilities versus boundaries or limits. • Confirm whether submarine pipelines/cables in that chart area are labeled with text (e.g., PIPELINE, CABLE) or symbols and if the dashed line at 390.5 has any such label. • Check if there are any named dikes or fields (such as Browns Field) nearby whose boundaries or limits might be indicated by that specific dashed line.