单项选择题
On the all-purpose nozzle，the position of the valve when the handle is all the way forward is（）.
A.shut B.fog C.solid stream D.spray
单项选择题 On a vessel carrying grades A，B，C or D cargoes，enclosed spaces where sources of vapor ignition are normally present shall NOT be segregated from cargo tanks by（）.
单项选择题 Oil may NOT be transferred unless（）.
单项选择题 Of the following，the most important consideration for a tanker is（）.
