??2??18?????????????? (???????????? ??)????????????18????,????????????????????????,???????????“???”,??????,???????“?????”????????,???,????

????????“?”????????????????????,???????????????,??????????,????????50???(?????)??????,?500??????,????????????1-3???,??????????????0.3%-0.5%/???????,???????????,???,?????????????,????,????

?????????????,“??????????????????”????????????????????????????????????,?????,?????,????????????20?(????????)?0.3%/????????,20?????????0.5%/???????????????????????????????????

??,?????“???????????????”??20?????(???????)?????????????????????,????????????20???????,???????????????????,??????????????????????????????????????????????????????????????????(??) ???:??????

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