Fill in the blanks with the help of words given in the bracket after each sentence.

(1) When air is contaminated by ________ substances which have a ________ effect on both the ________ and _______, it is referred to as ________.

(2) Many _______ are responsible for causing ________ pollution. Petroleum ________ are a major source of _______ pollutants like _______ and ________.

(Sulphur dioxide, refineries, industries, nitrogen dioxide, gaseous, liquid, people, air ).

(3) While ________ your teeth, leaving the ______ running may waste several ______ of water.

(tap, litres, brushing, washing, drops ).

(4) Water which is suitable for _______ is called _______ water.

(washing, bathing, drinking, potable, soft).

(5) Water which looks clean still has disease carrying _______ and _______ impurities.

(insects, micro organism, particles, dissolved, harmful).