If your vessel is underway in fog and you hear one prolonged and three short blasts，this is a （）.
A. vessel not under command
B. sailing vessel
C. vessel being towed (manned)
D. vessel being towed (unmanned)
查看答案
若按基准统一的原则选择定位基准，那么所有工序都必须选择同一基准。
A. 正确
B. 错误
The sign used to caution persons approaching the gangway of a tank barge during cargo transfer reads（）.
A. Warning，Keep Off，Stay Clear
B. Danger，Do Not Board
C. Warning，No Smoking，No Open Lights，No Visitors
Dangerous Cargo Being Transferred
简述多间隔保护采用直接采样和网络采样的同步原理；保护采用直采和网采对smpcnt、smpsynch位处理的差异。
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