A.Dead-reckoning positionB.Estimated positionC.FixD.Run……

单项选择题Uncharted lights，fog signals and radar beacon transmissions may be（）near the station.

A.encountered
B.met
C.contacted
D.seen

单项选择题Two navigational hazards are located near to each other，but each is marked by an individual cardinal buoyage system. The buoys of one cardinal system may be identified from the other system by（）.

A.the differing light colors
B.one system having odd numbers while the other system has even numbers
C.one system using horizontal bands while the other system uses vertical stripes
D.the difference in the periods of the light

单项选择题This is（）where we shall anchor.

A.the light-house
B.the anchorage
C.the pilot station
D.the light-buoy

单项选择题There is sufficient anchorage for（）at all time around the No.1 buoy and for smaller vessels around the No.4 buoy.

A.deep laded vessels
B.deeply load vessels
C.deep loading vessels
D.deeply loaded vessels

单项选择题The shortest distance between any two points on earth defines a（）.

A.small circle
B.great circle
C.rhumb line
D.hyperbola