On a Mercator projection chart, where do you read the longitude of a plotted position?

A. From the compass rose outer ring
B. From the latitude scale at the working latitude
✓ From the top and bottom scalesCorrect
D. From the side (left and right) scales

Why C is correct

On a Mercator chart, longitude is read from the top and bottom scales; latitude is read from the side scales. The compass rose is used for reading true or magnetic courses, not coordinates.

Cited:Bowditch Ch. 4 §405

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