                 .

	       
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.        ,
          
 .
	        :

--------------------------------
| .........       |
| ..........       |
|............(,,)...       |
|..........(,,)...       |
--------------------------------

F1  F2/+  F3  F4  F10 

	     
 .  " "   , 
      ,  
   " ".  "" 
 ,     
 (    "-")    
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       F2  .

	   F2,    :

-----------------------------
|   ?|
|                      |
-----------------------------

	         
        
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