Determine the course per standard magnetic compass from 0.2 mile south of Race Rock Light (LAT 41°14.6'N, LONG 72°02.8'W) to the entrance of the channel to Lake Montauk (west of Montauk Point).
• Great-circle vs. rhumb line is not an issue at this short distance – assume a straight line on the chart • Using variation and deviation steps in the correct order: True (T) → Magnetic (M) → Compass (C) → Standard compass (psc) • Carefully identifying the correct Lake Montauk entrance buoy/sea buoy shown on your exam chart, not Montauk Point Light itself
• After you plot the two positions on the appropriate training chart, what is the true course (°T) from the starting point to the Lake Montauk channel entrance? (Measure carefully, to the nearest 0.5° if needed.) • Given the variation in that area and the deviation from the deviation table for that heading, what is the correct sequence of conversions from °T to °psc? Are you adding or subtracting at each step? • Which of the answer choices is closest to the properly converted standard compass course, after you have accounted for both variation and deviation and rounded according to exam convention?
• Verify the exact charted position of the Lake Montauk entrance symbol or sea buoy before drawing your course line. • Check the local magnetic variation from the exam chart and be sure to apply the correct east/west sign: "east is least, west is best" (for converting between True and Magnetic). • From your vessel’s deviation table, confirm the correct deviation value for the resulting approximate heading, and apply the right sign before choosing the closest °psc answer.
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