Answer: c
Explanation: because it helps by excreting 
 
        
             
        
        
        
Same number of atoms on the outer shell, will have similar melting and boiling properties
        
             
        
        
        
Answer:
Cockroach is you answer.
Explanation:
They do this by using a very efficient breathing system that uses air filled tubes, called trachea, to deliver oxygen directly to cells. Oxygen flows in as required into the tracheal system through valves on the insect, called spiracles. But, sometimes, they shut their spiracles and stop breathing.