单项选择题
A.articulated anchor B.Flipper Delta anchor C.Baldt anchor D.Danforth anchor
An example of a messenger is a（）.A.fairleadB.heaving li...
单项选择题An example of a messenger is a（）.
A.fairlead B.heaving line C.stay D.warp
All electrical appliances aboard a vessel should be gro...
单项选择题All electrical appliances aboard a vessel should be grounded to（）.
A.prevent them from falling when the vessel rolls B.protect personnel from electrical shock C.increase their operating efficiency D.prevent unauthorized personnel from operating them
All echo-sounders can measure the（）.A.actual depth of w...
单项选择题All echo-sounders can measure the（）.
A.actual depth of water B.actual depth of water below keel C.average depth from waterline to hard bottom D.average depth of water to soft bottom
