????????????????????

??????

?????????????顢????

1.?????????30??????????????????????45.60.75.90???????????????

2.????????10???ж????ж??????0??????10?Σ?????ж?(???.????)???????ж?????

3.????????????????????????????????????????????????????????????0??????л??????????

4.???????????а???????????0????????????????50%????????????????????????????????????????????????????????????100%???????г齱???齱???????????50%??