航海英语号灯与号型单项选择题每日一练(2019.01.16)

单项选择题
A power-driven vessel towing another vessel astern (tow less than 200 meters) shall show （）.
A.three masthead lights in a vertical line instead of either the forward or after masthead light
B.two masthead lights in a vertical line instead of either the forward or after masthead lights
C.two towing lights in a vertical line at the stern
D.a small white light aft of the funnel
单项选择题
A 200-meter vessel is aground in fog. Which signal is optional? （）
A.A bell signal
B.A gong signal
C.A whistle signal
D.All of the above
单项选择题
A towing vessel 30 meters in length is pushing barges ahead. How many white masthead lights is the vessel REQUIRED to show at night?（）
A.One
B.Two
C.Three
D.Four
单项选择题
A vessel towing is showing three forward white masthead lights in a vertical line. This means that the length of the（）.
A.towing vessel is less than 50 meters
B.towing vessel is greater than 50 meters
C.tow is less than 200 meters
D.tow is greater than 200 meters
单项选择题
The prohibition against displaying lights which may be confused with required navigation lights applies（）.
A.from sunset to sunrise and during restricted visibility
B.only when other vessels are in the area
C.only when operating in a traffic separation scheme
D.only when under tow