?? ?????????????????U20?????????????
![](http://n.sinaimg.cn/news/transform/200/w600h400/20180324/B96n-fysnevm3872686.jpg)
????:1??????????:???????????
2???????????
3?????????????
4???????????????
5?????????
?????2???????????????????13????????? (?)13?,???U20???????,????????????????,??
????,?????2??????????6????,????U20??????????????????????????????,???????????,??????????????,??4????
??,???,???????????????,???,???????,??????????????????????2???????7???????????????,????????,???????????????,??????????????S0S????????????????????????????????2???????????????8???,?????????,?????????????
??????????????????????,????2?10?????????????????,??????????????????,??????????????????????????????????????2?12??????????,??????,?????????????????????????,????????????????
??????????,??????,????,?,?????(?????????) ??:?????????????