{  ,       100   }

 1:

-     (+10,   )
-  ,        (+90)
+    (+50)
-   (+40)

 2 ():

-    (+10)
+    (+40)
-   (+20)

 3 ():

-   ,      (+10 -  ,    )
-   ,      (+40)
+    (+30)
+     (+30)
-   (+30)

 4 ():

-   II (+30)
+    (+20)