You can't convert miles into gallons those are two different units of measurement.
        
                    
             
        
        
        
Answer:
uhm im really sorry about this but i really need points i would help but id get it wrong im bad aat math
Step-by-step explanation:
 
        
             
        
        
        
The length is 486
Step-by-step explanation:
638 subtract 152
 
        
             
        
        
        
75% I think. 
because if you do 560 - 420 you get 140.
140 / 560 x 100 = 25 
which means there is a 25% decrease, so they took 75%.
        
                    
             
        
        
        
If you ate a third of the box and there ARE 16 left then you started with 48 originally