1) Which of the following gases have great percentage in the atmospheric air........ a) O2 b) N2 c) Co2 d) H2o 2) Oxygen prcentes in the atmosphere gaseous state in form molecules structure....... a) O2 b) O c) O3 d) O4 3) Respiration and compassion process consume....... Gas a) O2 b) N2 c) Co2 d) Ar

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