                           
     1.                                                   
    2.                                           400    200          
     3.                                                   
     4.                                                               
     5.                            6  7         

    6.                                 
     7.                                           
     8.                                 
     9.                                                                     
    10.                    
    11.                                             30              
    12.                 6                          
    13.                            
    14.                              
    15.                                     
    16.                                                      250      8       
    17.                                         
   18.    :                                 
   19.                                    
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