?? 7???70???????
![](https://image.chezhanri.com/2019/0725/20190725164453543.jpg)
????:1???????:???????60??
2????????
3?????
4?????????
5??????????
???????????????????8???????????15???????????????? (?????????? ?????)7??,????70??????????????
?????15???????????????????????,7?????????,??????????70??????,?????
????????,7????,70????,??????????????2??????????????????;???????1?????????????????????,7?,70?????????0.65%,???????????0.03?????;70??0.8%,???????????????????0.05????
???,7???;??????????????,?????????????,????????????????
??,7????????????????,?????????????????????;????????????,??5????????????????????????70???????,?,????????????????????????????????,???
58??????????,??7????????????46??????????????????“??????”(??????)??,????,??,??0.36,????,???
???,??????????????????????“???????”?????????,???????????????(??) ???:???