单项选择题
A.Hydrus B.Leo C.Centaurus D.Aquila
Deneb is found in what constellation?（）A.CygnusB.Pegasu...
单项选择题Deneb is found in what constellation?（）
A.Cygnus B.Pegasus C.Ursa Major D.Andromeda
Define the acronym MSI（）.A.Maritime Safety InformationB...
单项选择题Define the acronym MSI（）.
A.Maritime Safety Information B.Maritime Shipping Index C.Maritime Satellite Indicator D.Mariner Safety Intelligence
Deficient oxygen content inside a chain locker can be d...
单项选择题Deficient oxygen content inside a chain locker can be detected with（）.
A.litmus paper B.combustible gas indicator C.oxygen breathing apparatus D.oxygen indicator
