?? ?????????????????????3.46?????
![](https://image.chezhanri.com/2019/0605/20190605164025339.jpg)
????:1??????:??????????
2????????
3??????
4??????
5????????vx
??????????(6??19???)????????,??????????????????
??3.46????????????,????,
???????????????????????????????7??????????????(???????)2.13???,???????????????????,??;
???????????????????4??(??????????????)0.69????????????????,??,?,????????????,????;
???2????????????0.64?????????????,??,??????
(?????????? ?? ?) ??:????