Attention is called to the fact that in many cases pipelines are not （） and charted depths may be decreased by up to 2 meters．

单项选择题Attention is called to the fact that in many cases charted depths may be decreased by up to （）.

A.one nautical mile
B.two kilometers
C.5 cables only
D.one fathom

单项选择题At last，the palm trees that fringe the natural harbor of Port Aloahoa come into view on the horizon lit by the setting sun.The meaning of this sentence is that （）.

A.a vessel arrives at a port in a evening
B.a vessel leaves a port in a evening
C.a vessel arrives at a port in a morning
D.a vessel leaves a port in a morning

单项选择题As these features are not all charted，special caution should be exercised （） vessels navigating in the vicinity.

A.by
B.with
C.on
D.in

单项选择题Areas enclosed by a long and short dashed magenta line indicate （）.

A.cable areas
B.dumping grounds
C.fish trap areas
D.precautionary areas

单项选择题An occulting light is one in which （）.

A.the period of darkness exceeds the period of light
B.there is only a partial eclipse of the light
C.the periods of light and darkness are equal
D.the period of light exceeds the period of darkness