21.   Some have turned to incineration, but burning is controversial because it releases toxic gases.

22.   The authorities said a construction crew laying fiber-optic cable accidentally ruptured the line, releasing gas into the air.

23.   The apple will release ethylene gas, which accelerates ripening.

24.   The cave-in apparently released methane gas.

25.   The electric ovens will heat the samples to see what gases are released.

26.   The gas is released either by pressing a panic button, or automatically when a tilt sensor makes an electrical circuit.

27.   The particular subway cars where gas was released were reportedly those that would be closest to the subway exit used by people going to the police agency.

28.   The pop was the sound of the bubbles as they released their gas at the surface.

29.   The particular subway cars where gas was released reportedly were those that would be closest to the subway exit used by people going to the police agency.

30.   They let the media hang out in the parking lot where the gas was released, destroying evidence such as wheel marks.