I'd say look at photos of them from a front, and sideways view :)
        
             
        
        
        
1:Violin 
2:Viola
3:Cello
4:Double bass
        
             
        
        
        
Answer:
what did Cleisthenes do in 510 BCE how was Greek society in Athens changing at this time
Explanation:
 
        
             
        
        
        
A system called Khipus to record statistical info c:
        
             
        
        
        
One technique is that the front objects are larger and lower than than the background