The answer is (A. mitosis) 
 
        
             
        
        
        
Answer:
Body
— Right atrium Right ventricle - Lungs – Left atrium Left ventricle - 
Explanation:
 
        
             
        
        
        
It should be Ozone, hope that helps. 
Trees release CO2 which is Oxygen.
Plants release water vapor through Photosynthesis. 
        
                    
             
        
        
        
Answer:
a neutral solution? i think
 
        
             
        
        
        
The answer is <span>Topoisomerase.
Topoisomerase is an enzyme responsible for twisting of DNA helix. After DNA strand is untwisted by helicase enzyme, DNA must be twisted again so the normal function of DNA can be sustained. If left untwisted, the replication fork will continue to grow, the normal function of DNA will stop.</span>