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??2???????????????18????????????? (?? ?????????????)?18??????,???????,?????“????????”,???????????????????????????????????????????,????????“?????????????”???,???????,?????????
???“???”???????????,??????????????????????????????????????????,???????,????????????50??(???)?????,??500?????????,??????1-3??,????????0.3%-0.5%/????????????????,????????????????,??????????,????????,??????????????????,???????
?????,“????”????????????????????????,????????????????,?????,??20??(??)??????0.3%/??,20??0.5%/????????????????????????????????????????????????????????????
???????,??“?????”???20???(???????????????)?,???20?,??????????,???????????????????????????????????????????????????????(???????????) ???:??
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