Methane and air explosions occur in the well-known mixture range of 15% to 25% methane in air.

Methane and air explosions occur in the well-known mixture range of 15% to 25% methane in air. A: 正确 B: 错误

There’s a feeling of unrest nowadays. A: in the air B: on the air C: by air D: in air

4. From the control tower, air traffic controllers coordinate aircraft movement both ________ and on the ground. A: on the air B: in the air C: at the air D: of the air

Methane and air explosions occur in the well-known mixture range of 5% to ( )% methane in air. A: 10 B: 15 C: 20 D: 25

智慧职教: Compressed air is supplied by air compressors to air receivers.

An air waybill is used for air transport. It is an evidence of a ( ).

The air leakage of tubular air preheater is larger than that of rotary air preheater (). A: Right B: Wrong

What is the talk mainly about A: The definition of air pollutant. B: The causes of air pollution. C: The dangers of air pollutants. D: Ways to fight air pollution.

In an operating diesel engine, which of the following conditions is an indication of a leaking air starting valve? A.Noise coming from that air starting valve B.Continuous operation of the starting air compressor C.Zero air pressure in the air starting system D.Overheated starting air pipe to the cylinder head