1. Aerobic oxidation is caused by

1. 1. aerobic batteries in presence of excess of oxygen

   
   
   

   2. anaerobic bacterias in presence of insufficient oxygen

   
   
   

   3. aerobic bacterias in the absence of oxygen

   
   
   

   4. both anaerobic and aerobic bacterias in any condition

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: A

   NA

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2. Which one of the following statement is correct ?
   Ozone is found in the earth's atmosphere mostly between

1. 1. 5 and 10 km

   
   
   

   2. 10 and 20 km

   
   
   

   3. 20 and 50 km

   
   
   

   4. 50 and 100 km

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: C

   NA

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3. Main source of lead pollution is from

1. 1. sewage

   
   
   

   2. leaded gasoline

   
   
   

   3. tobacco

   
   
   

   4. insecticides

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: B

   NA

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4. Which of the following is secondary air pollutant ?

1. 1. Photochemical smog

   
   
   

   2. NO₂

   
   
   

   3. Dust particles

   
   
   

   4. SO₂

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: D

   NA

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5. Which of the following is a secondary pollutant ?

1. 1. NO

   
   
   

   2. CO

   
   
   

   3. SO₂

   
   
   

   4. PAN

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: B

   NA

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