60. Stall type urinals are best - | 10;
(A) high schoals (8) residential houses
(C) people of same height (D) public places
61. Of the total content ए watex on globe, the available quantity for use is less than :
(മ) 20% ® 2% (©) 0.03% യു 01%
62, All water that occurs below the surface of the earth is called :
(^) Ground water (B) Underground water
(©) Surface water (D) None of the above
63. In sewage treatment plants, the oil and grease is r....
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