Pls help with this questions.?

oxygen first one, , carbon dioxide second one.

breathes oxygen, fish, use labyrinth in gills pull oxygen out of water.
normal amounts of co2 in atmosphere acts natural greenhouse traps heat , maintains comfortable temperature. commonly known problem of greenhouse gas buildup causing global warming due excessive emissions of co2, primarily, , other gases atmosphere.

a) important gas living organisms or human beings ?
b) gas important gas controlling weather , climate ?

Science & Mathematics Geography Next