https://www.youtube.com/watch?v=RTS9vYJ8tmk
https://www.youtube.com/watch?v=k3NGJG_7r0s
: 2 . 0,5 . 1 . 1 1 . 0,5 . 2-3 ,, . , . . , 20-30 . , ... ! ...
, - ... ....
: