The period of a lighted aid to navigation refers to the（）. -题库考试答案搜索网

The period of a lighted aid to navigation refers to the（）.

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2023-03-05 20:10

A、date of construction or establishment
B、length of time between flashes of the light
C、time required for the longest flash of each cycle
D、time required for the light to complete each cycle

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标签：地文航海

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