Question

For example, when people burn fossil fuels, pollutants can enter the atmosphere and mix with the water vapor that is to form clouds. This polluted water falls to the surface as acid rain. carries the polluted water by gravity along the Earth’s surface.

Answer 1

Condensing & runoff are your answers. 

Answer 2

Answers

Condense and Runoffs

Explanation

An increase in burning of fossil fuels such as coal and petroleum products releases pollutants in form of gases which enter the atmosphere. When these gas particles reach higher atmospheric heights, they mix with water vapor and  condense to form clouds. When the clouds get heavy, precipitation occurs inform of rainfall. The rain water forms acidic rain due to pollutants in the air which fall to the surface. Runoffs carries the polluted water by gravity causing chemical corrosion to occur on iron sheets in our roofs.