I believe it’s a because something cannot move unless a force is acted upon it
        
             
        
        
        
Answer:
about 0.9 mol
Explanation:
there are 22.990 g/mol of Na 
20.7/22.99 = 0.900391 mol
about 0.9 mol
 
        
             
        
        
        
Examples that have been believed to be science: such as religion, flat earth, etc.