Question 437 Rules of the Road

90% to pass

INTERNATIONAL ONLY If a vessel displays three all-round red lights in a vertical line at night, during the day which shape(s) may she show?

A A cylinder
B Two diamonds in a vertical line
C Two cones, apexes together
D Three balls in a vertical line
AI Explanation

The correct answer is A) A cylinder. The International Regulations for Preventing Collisions at Sea (COLREGS) state that a vessel displaying three all-round red lights in a vertical line at night is a vessel "not under command." During the day, such a vessel must display a shape consisting of a cylinder. The other options are incorrect because they do not match the dayshape required for a vessel displaying three vertical red lights at night. Two diamonds, two cones, or three balls would indicate different light configurations or vessel statuses under the COLREGS.

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