Steam rises to the top and stays there
        
             
        
        
        
The answer should be; 11
The atomic mass number is found by combining the number of protons and neutrons
Hope this helps :)
 
        
                    
             
        
        
        
The second brother Brother because he is much heavier and therefore has more energy to be released hope this helps
        
                    
             
        
        
        
Answer:
A pure substance has a definite chemical composition
 
        
             
        
        
        
All of them are compounds.