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

2?????????

3?????????

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5????????

???????11?????30??? (? ?????)???????????????????30??,11??50%,?????????????????????0.2????,????6??50%???,????

?,????,?????????????????0.3??0.9????????;??????????????;?????????????????????????????????????????????????????

???????????,11??????????????,????50%,????????,?????,??????60%????????????????,???????????????;??????????????????????52%?????,???????;??55%????,??????????????????????,???

??,??????????,??????????,?????????????????,???????????????????????????????????????,??????????????11??,????????????????,??????(??) ????????????????:?????????????????