✔ . 500 , 300 , 100 , 4 . 1 . ., 1 . . 3 , . . . ✔ . . , . ✔ . 2-3 . 3-4 . ! ✔ . 1/4 , . 2 2 . . ✔ . 1/2 1 , 1 . . . 1/3 3 20 . .