Ⅱ            80  
           20  
                             2    10  
19.                           
     2  
A. B.
C. D.
20.              2  
A.           
B.           
C.           
D.           
21.                      2  
A.          B.        
C.         D.         
22.               2  
A.    +  +  +  B.    +  +  +  + 
     +  +  +         +  +  +  + 
C.    +  +  +  +  D.    +  + 
     +  +            +  +  + 
23.             2  
A.                 
B.                 
C.                               
D.                         
      10  
24.             2  





25.         2  
⑴                  


⑵          


26.            3  
          
     
     
      
27.   8        3  
                                                                       
  

       60  
28.                         
 
①     
②     600   
③   40          
④             A  B                  X  Y       