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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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