🔍 Key Concepts

• Difference between physical diameter and cross-sectional area of a conductor • How American Wire Gauge (AWG) sizes are actually defined • Traditional electrical-engineering unit used for conductor area in older marine and industrial standards

💭 Think About

• Which of these options is a numbering system rather than a direct unit of area? • Which option represents area (length squared) instead of a single length dimension? • In marine electrical tables, what unit is used when calculating ampacity or resistance based on conductor size?

✅ Before You Answer

• Identify which choices are length units versus area-related units • Recall that AWG wire sizes are based on a special unit that combines diameter squared with a constant factor • Verify which unit you would expect to see in older NEC/marine cable tables for conductor size by area