Scientists use a Graduated Cylinder
        
                    
             
        
        
        
Answer:
answer of your question is 4th
Explanation:
P205
 
        
             
        
        
        
The main difference between the 3 isotopes of hydrogen are the number of neutrons in the nucleus. Hydrogen has no neutrons, Deuterium has one neutron, and tritium has two neutrons. All three have one proton and one electron.