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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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