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

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

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

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

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