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

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

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

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

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