6. 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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7. 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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8. Saline soil contains

1. 1. high concentration of salt

   
   
   

   2. lot of moisture

   
   
   

   3. hard rocks

   
   
   

   4. none of the above

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: A

   NA

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9. Higher concentration of nitrogen dioxide in atmosphere air causes

1. 1. cancer

   
   
   

   2. bronchitis

   
   
   

   3. asphyxiation

   
   
   

   4. corrosion

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: B

   NA

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10. A fertile soil is likely to have a pH of

1. 1. 3

   
   
   

   2. 9

   
   
   

   3. 6-7

   
   
   

   4. 14

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: C

   NA

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