单项选择题
A.uncorrected KG
B.maximum allowed KG
C.virtual height of the center of gravity
D.metacentric height
单项选择题 In which case is the IOPP Certificate of an inspected vessel NOT invalidated? （）
单项选择题 In setting the valves on a steam-smothering system on a tanker，the master control valve to cargo tanks should be（）.
单项选择题 In order to reduce the accumulation of static electricity while loading petroleum products，you should（）.