单项选择题
When may the automatic identification system (AIS) be switched off? （）
A.At anytime as long as it is properly logged B.At the Master's professional judgment C.Only when the vessel is at anchor or in port D.Under no circumstance
单项选择题 When communicating on the radiotelephone using plain English，what procedure word indicates the end of my transmission and that a response is necessary? （）
单项选择题 To reduce the amount of catenary you may（）.
单项选择题 The Vessel Bridge-to-Bridge Radiotelephone Act applies to which towboat?（）
