                                                      
             2          1         0   
   1.        
   2.        
   3.            
   4.            
   5.        
   6.          ×   400    
   7.             
   8.            
   9.         
  10.        
  11.                 
  12                  
  
  0 9                  
  10 15              10               
  16 24              12                           