:
= 2 .
= 1 .
=1 . .
= ¼ ;
= 50
=500
=2-3
(4-5 )
=2-3 .
=2-3 . .
=4-5 ..
=
*** . , , , . , . , . .
*** , . , , . , .
*** . , , , , . 180 , 30 . !