               .

	    ,    :

--------------------------
|.(,,)....          |
|.(,,)...          |
|.(,,).....          |
|.(,,).          |
| ..          |
| (0,20,+)..          |
--------------------------

F1  F2/+/-   F3  F4  F10-

	      . 
     ""   ,  
  .       .
 ""        
      .   
,          
   .   "0",     .
  20,      20%.  
"+",        .
             
     .
               ,  
        F3.
         
   .     
   Enter,       
    .      
      .
               
           
  .      
  ,      
    F4    .

	      (F2  "+"),   
 :

----------------------------------------
|   .     |
|    .|
|.                                |
----------------------------------------

	    "Enter".  
:

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

	
	    "Enter".   
        
   .      
       
 .

	     "-",    
     .     
.