800m is greater than 799,999mm
        
                    
             
        
        
        
You go through and square each term in the parentheses 
(12a^2b^6)^2 = (12)^2(a^2)^2(b^6)^2 = 
144a^4b^12
        
                    
             
        
        
        
you will have 10 if im mistaken it is 5 i hope this is kinda helpful im only in 6th grade sorry if it is wrong
 
        
             
        
        
        
20 ÷ 2 (5,5)
20 ÷ 2 (25)
20 ÷ 50
.4