The air that we breath is about 20% oxygen, and small amounts of carbon dioxide. Since the air is 78% nitrogen I would say false. Also, I would say false because we inhale oxygen then exhale carbon dioxide for plants to inhale, then they exhale oxygen for us. Its the circle of air. So when the question asks if the air we breath is mostly oxygen and carbon dioxide it is wrong cause we dont breath in carbon dioxide, I mean we do breath it in but we dont use it. We just exhale it back out. Just take what i have right now before I confuse you :)
Hope I helped :)
