If there has been a fire in a closed unventilated compartment it may be unsafe to enter because of _________.
A:unburned carbon particles
B:excess nitrogen
C:a lack of oxygen
D:excess hydrogen
C
解析:封闭舱室内若发生过火灾,因为内部缺氧,人员进入会很不安全。
A:unburned carbon particles
B:excess nitrogen
C:a lack of oxygen
D:excess hydrogen
C
解析:封闭舱室内若发生过火灾,因为内部缺氧,人员进入会很不安全。