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

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

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

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

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