I think sister groups. Imagine them having the same parents.
        
             
        
        
        
12/44 = 0.2727
(X100)
= 27
( therefore the percent mass of carbon in carbon dioxide is 27%)
        
             
        
        
        
I am sure the answer is repel because human hair carries negative charges which mean they will repel because like things repel
        
                    
             
        
        
        
White Blood cells or WBC's are the cells of your immune system. They are your first defense in fighting off foreign invaders and infectious diseases.
-Medical Student (College Level)