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1. The movement of air helps to rotate windmills for electricity generation.
 
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Windmills
 
Moving air turns the blades of windmills to run mills and draw water from tube wells by running pumps.
 
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Windmill running a pump
  
2. Air is used to sail yachts, fly gliders, aeroplanes, parachutes, etc.

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A man flying a glider
 
3. Plants and animals utilise air for breathing. Also, air helps birds, bats and insects to fly.

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A flying bird
  
4. Air is also used in the dispersal of seeds, and it acts as a pollinating agent.
 
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Dispersal of seeds
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5. Air plays a vital role in the water cycle process, which gives us rain.
 
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Water cycle
 
6. Air is used in the combustion of fuels like wood, coal, kerosene, LPG etc. It is also compressed to fill the tyres of vehicles like cycles, cars, etc.
 
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Burning of wood and pumping air into cycle tyre
 
7Ozone layer in the atmosphere prevents harmful radiations of the sun from reaching the earth’s surface.
 
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Sunlight falling on Earth
  
8. Under some emergencies, patients with breathing difficulties use oxygen masks and cylinders for breathing.
 
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A patient wearing oxygen mask
 
9. As the height (altitude) increases, the air becomes thinner. Hence, mountaineers or people who climb the mountains carry oxygen masks or oxygen cylinders with them. Deep-sea divers also carry oxygen cylinders for breathing under the sea.
 
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A mountaineer and a deep-sea diver
Reference:
https://upload.wikimedia.org/wikipedia/commons/e/e8/Simple_face_mask.jpg