? ???2? ? ???? ??? ? ?2????

??? ???2??

?????????????????????? ??????? ?2????????????????

???? ?????????2??????

???????????????? ???? ?? 1/3

??12???????20??,???,??2??,??60????????????????????????????????????????

?????????????:????

????? ?? “???????”????

?? ? ????????????????2???????

????:1????????:?????????

2?????????

3???????

4????????

5?????????

? ???2? ? ???? ??? ? ?2????

??? ???2??

?????????????????????? ??????? ?2????????????????

???? ?????????2??????

???????????????? ???? ?? 1/3

??12???????20??,???,??2??,??60????????????????????????????????????????

?????????????:????

????? ??