246.  The layers of vegetable wastes and night soil alternatively piled above the ground to form a mound, is called
A. a heap
B. platen
C. windrow
D. none of these.

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247.  In a fully mechanised composting plant, involves
A. mechanized receipt
B. mechanized segregation
C. mechanized pulverising of refuse
D. all of these.

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248. Depletion of ozone layer in the outer atmosphere may cause
A. lung cancer
B. skin cancer
C. bronchitis
D. heart disorder.

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249. Which one of the following part of human body withstands minimum radiation
A. thyroid
B. kidneys
C. eyes
D. ovaries/testis.

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250. Which one of the following gases is most significant as air pollutant
A. Carbondioxide
B. Oxygen
C. Nitrogen
D. Sulphurdioxide.

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251. A rainfall may be classified as acidic if its pH value is less or equal to
A.6
B.7
C.5
D. 6.5.

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252.  The most dangerous pollutant in vehicular emissions is
A. CO
B. SO2
C. CO2
D.SO

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