??????? ???????????15.3?

?2??17??? (? ???)?17???,??,2?????????????13?16????????,???????????????,???72??15.3?,??;?????????????????????10??????????48???????????6.5?~10.9???,????;??????????????????????4???????

???????????,??????????????????,??????????

??2????????????18????2??22???,?????????????,???????????????,?????2???????19???2?????????????????20???,??,??????????????????????,?????????????,??????????,?????????(?)