????????????20??????

????:???????py:???????

???????8????31?????????????????????? (????????????? ?????????????????)??????8??31?????????????????,8???????????????50.3%,??????20???50%??,???????????

???????????????,???????????????????,?????????????????0.6?????0.1??????;????????????????????????????????????????????,??????????????????????0.3?2???

??,8?????,???????50.3%,??????20???????????????50%??????????????,????????50%??,???????

?,?????8???,?????????????50.2%,??????0.2??????????????????????,???????????,???????,??????

?????,???????????????????,???????????????????????????55%????????;?????????????????,??,??????????????60%????????????????????

???,???,?????,?????????????,????????,???????????(??) ??????????????????:?????