The correct answer is A....
Answer:
1 Photosynthesis uses CO2 and expels O2 and the reverse for respiration
2. stratosphere where ~90% of it is
3. Less infrared radiation is able to escape from the earth into space and that infrared radiation hits the GHG gases and the radiation is turned into kinetic or heat energy trapping which warms up the earth
Explanation:
Many scientists agree that the universe is about 13 billion years old.
I think its false because gas exchange can happen in blood also
