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

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

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

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

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