1) Gases which make up the bulk of the atmosphere a) Helium & Ozone b) Nitrogen & Oxygen c) Argon & Hydrogen d) None 2) Gas needed for burning  a) Nitrogen b) Helium c) Oxygen d) Water vapour  3) Plentiful gas in the air a) Nitrogen b) Oxygen c) Atmosphere d) None 4) The amount of Carbon di oxide gas present in air. a) More than 1℅ b) Less than 1℅ c) 21℅ d) 70℅ 5) We need this gas for breathing. a) Nitrogen b) Carbon dioxide c) Oxygen d) Water vapour 6) Property of air a) Air has no weight b) air occupies space c) air cannot lift up things d) air is everywhere  7) warm air ———- and cold air ———. a) sinks, rises up b) moves out, moves in c) moves in , moves out d) rises up, sinks

air

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