Fill in the blanks.

(a) Burning of wood and coal causes …………… of air.

(b) A liquid fuel, used in homes is ……………

(c) Fuel must be heated to its …………… …………… before it starts burning.

(d) The fire produced by oil cannot be controlled by ……………

(a) Burning of wood and coal causes pollution of air.

(b) A liquid fuel, used in homes is kerosene

(c) Fuel must be heated to its ignition temperature before it starts burning.

(d) The fire produced by oil cannot be controlled by water..