单项选择题
A.odd or even numbers B.the color of their top band C.the location of the buoy in the channel junction D.the buoy's light rhythms
Lighted white and orange buoys must show which color li...
单项选择题Lighted white and orange buoys must show which color light?（）
A.Orange B.White C.Red D.Alternating yellow and white
In plotting a running fix，how many fixed objects are ne...
单项选择题In plotting a running fix，how many fixed objects are needed to take your lines of position from? （）
A.Three B.Two C.One D.None
At the magnetic equator there is no induced magnetism i...
单项选择题At the magnetic equator there is no induced magnetism in the vertical soft iron because（）.
A.the lines of force cross the equator on a 0°-180°alignment B.the quadrantal error is 0° C.there is no vertical component of the Earth's magnetic field D.the intercardinal headings have less than 1°
