单选题A vessel showing a green light over a white light in a vertical line above the level of the sidelights is（）.A engaged in underwater constructionB under sail and powerC a pilot vesselD trawling

An anchored vessel on pilotage duty must show which light(s) at night?

A.A sternlight only

B.Anchor lights only

C.A white light over a red light only

D.A white light over a red light and anchor lights

A vessel showing a green light over a white light in a vertical line above the level of the sidelights is ______.

A.engaged in underwater construction

B.under sail and power

C.a pilot vessel

D.trawling

A list man would expect to see any of the following light signals EXCEPT ______.

A.two red lights

B.one green light

C.one white light

D.one amber light

The Coordinator Surface Search（CSS）in a SAR situation should display by night ______．

A.Deck lights forward and aft

B.A white light over two red lights

C.A red light，white light，and blue light in a vertical line

D.A distinctive signal promulgated by the CSS

A vessel may use any sound or light signals to attract the attention of another vessel as long as ______.

A.white lights are not used

B.red and green lights are not used

C.the signal cannot be mistaken for a signal authorized by the Rules

D.the vessel signals such intentions over the radiotelephone

A vessel trawling will display a ______.

A.red light over a white light

B.green light over a white light

C.yellow light over a red light

D.white light over a green light

A list signal of one white light indicates that the vessel is ______.

A.on an even keel

B.listing about 1° to the side the light is displayed on

C.listing over 5°With the light displayed on the high side

D.listing，and the chutes should be directed to the side where the light is displayed

A buoy marking a wreck will show a(an) ______.

A.white light FL (2) and a topmark of 2 black spheres

B.occulting green light and may be lettered

C.yellow light and will be numbered

D.continuous quick white light and may be numbered