Answer: As matter cycles and energy flows through living systems and between living systems and the physical environment, matter and energy are conserved in each change. The carbon cycle provides an example of matter cycling and energy flow in ecosystems.
Explanation:
 
        
             
        
        
        
I think it’s nucleic acid
        
             
        
        
        
Answer:
12. which is used to measure ocean depth the answers is C
Explanation:
 just because