Preheating of __________ the flame temperature.
(A) The gaseous fuel before combustion decreases
(B) Combustion air decreases
(C) Either the fuel or the air or both, increases
(D) Either the fuel or the air does not affect
(A) The gaseous fuel before combustion decreases
(B) Combustion air decreases
(C) Either the fuel or the air or both, increases
(D) Either the fuel or the air does not affect