????:1?????300????:???????

2?????????

3???????95????

4??????????

5???????????

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

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

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

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