单项选择题
A.That B.It C.Which D.What
（）tankers over 100 meters long must not proceed beyond ...
单项选择题（）tankers over 100 meters long must not proceed beyond Dongbei Buoy.
A.Loading B.Load C.Lade D.Laden
International distress signal in VHF calling for help i...
单项选择题International distress signal in VHF calling for help is（）.
A.Help，Help，Help B.Mayday，Mayday，Mayday C.Save，Save，Save D.Rescue，Rescue，Rescue
There are salvage operations（）position 120.0N 12.5E.A.o...
单项选择题There are salvage operations（）position 120.0N 12.5E.
A.on B.at C.in D.above
