Study the graph. Explain how is oxygen concentration affected in the river when sewage is discharged in it.</h2>&l…

Which of the following is not a green-house gas?<br> </h2></div>

What is 'Greenhouse effect'?</h2></div>

The large-scale deforestation that is happening all over world is causing :</h2></div>

Multiple Choice Questions<br> BOD in river water<br> </h2></div>

Which of the following would happen in the absence of greenhouse effect in the atmosphere?</h2></div>

<span>The garbage or trash collected regularly is known as</span></h2></div>

Biochemical oxygen demand in a river water </h2></div>