A. flashing B. pulsating C. occulting D. alternating
A. fixed red light B. Morse (A) white light C. composite group-flashing light D. yellow light
A. gnomonic curve B. small circle C. meridian D. great circle
A. fixed red light B. flashing light C. white light D. occulting light
A. wreck B. shoal area C. anchorage area D. middle ground
A. Open-faced diamond B. Diamond with a cross Circle D. Square
A. a hard sand shoal marked with a light B. completely submerged at all stages of the tide C. surrounded by rocks awash at low water spring tides D. a small，low，sandy islet surrounded by shoal water
A. red and black bands B. green and black bands C. red and white stripes D. green and white band
A. removed B. altered C. corrected D. converted
A. from a submarine on the surface B. the light at Southeast Point C. at an airport D. on a coastal patrol vessel
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