Energy can only be transformed. You cannot destroy energy or create it. For example, the potential energy when you have something sitting on a desk doesn't disappear once it falls off. It gets TRANSFORMED into kinetic energy. This happens constantly. Energy, the ability to do work or cause a change, is always being reused in different forms. Hope this helped!
        
                    
             
        
        
        
Carbon is listed twice my dude :)
 
        
             
        
        
        
Eutrophication of water bodies like lake, pond, shallow stretches of river, etc. is the phenomenon where excess growth of vegetation on the surface of the water takes place. This excess growth results in the clouding of the water, depletion of dissolved oxygen in water, and the death of aquatic organisms. The primary reason for the cause of eutrophication is the presence of nutrients in excess amounts in the water. The nutrients B. come from fertilizer and sewage runoff. 
 
        
             
        
        
        
Photosynthesis puts oxygen in the atmosphere.