. 1 1 1 1 1 1 1 1 1 1 1 1 1 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 3 3 3 3 3 3 3 4 4 . 4.5 2.5 2.5 1 - 2 1 - 2 1 - 2 1 - 2 1 - 2 1 - 2