单项选择题
The lowest temperature at which a liquid gives off enough vapor to ignite in the presence of an ignition source is called its （）.
A.boiling point B.flash point C.viscosity point D.toxic point
单项选择题 An example of class "A" fire is a/an （）.
单项选择题 The most common type of containment device for spilled oil on the water is the use of （）.
单项选择题 A tank has been sealed and unventilated for a long period of timeWhich of the following conditions does this indicate?（）
