1) Air is a _________of gases. a) Solution b) mixture c) suspension 2) Which gas is present in maximum amount in the air? a) Chlorine b) argon c) nitrogen 3) Which as is essential for both plants and animals for breathing a) Helium b) oxygen c) Carbon di oxide 4) Moving air is called a) Wind b) hurricane c) tsunami 5) Water is present in the air in the form of _________ a) Water vapour b) dust c) smoke

AIR AROUND US 3

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