Fill in the following blanks with suitable words :
(a) A fuel must be heated to its___ before it starts burning.
(b) The most common supporter of combustion around us is___
(c) Fire produced by burning oil cannot be controlled by___
(d) A liquid fuel used in homes is___
(e) The amount of heat evolved when 1 kg of a fuel is burnt completely is called its___
(f) The substances which vaporise during burning, give___
(g) Burning of wood and coal causes___ of air.