Which one of the following is a cause of acid rains?

The desirable range of pH for drinking water is

Consider the following reaction, CH₄ + 2O₂ $$\to$$ CO₂ + 2H₂O. Which of the following about the reaction given above is/are correct?

1. Carbon is oxidised

2. Hydrogen is oxidised

3. Hydrogen is reduced

4. Carbon is reduced

Select the correct answer using the code given below :

Water boils at a lower temperature at high altitudes, because