单项选择题
A.Foam
B.Solid stream water nozzle
C.All-purpose nozzle
D.Carbon dioxide
单项选择题 When fighting a fire with a portable dry chemical fire extinguisher，the stream should be directed（）.
单项选择题 When fighting a fire on a bulkhead using a portable carbon dioxide extinguisher，the stream should be directed at the（）.
单项选择题 When fighting a fire in an enclosed space，the hose team should crouch as low as possible to（）.