The act of smothering a fire is to prevent air (oxygen) from feeding the flames.
removing the fuel or source of ignition.
using a flame extinguisher. Water won't be very effective against a tire fire. Smothering the fire would also work, if you have the means to cover it with a large amount of sand or something similar.
A class B or "Bravo" fire is any fire involving the combustion of liquids such as gasoline, diesel, liquid paint, solvents, or oils. These can usually be extinguished using some form of vapor seal over the liquid like aqueous film forming foam (AFFF, essentially REALLY soapy water that floats over any other liquid). Other extinguishing methods are smothering, and dry chemical extinguishing agents like PKP or Sodium Bicarbonate. Water is typically a bad choice of extinguishing agent for this type of fire since you may end up actually spreading it and making the fire worse.
No, it is not. Because hydrogen is flammable, it will burn in contact of the fire, instead of extinguishing it. So, generally the gas used for extinguishing fire is Carbon dioxide, which is neither flammable nor supports combustion
removal of fuel
The act of smothering a fire is to prevent air (oxygen) from feeding the flames.
water
For each fire and material exist a specific fire-extinguishing method.
At the base of the fire and use a sweeping motion
You get rid of the oxygen supply by smothering the fire with a a blanket or something.
No
extinguishing fire,dry ice