????:1???????:??????vx

2???????????

3????????

4????????????

5??????????

?:1???????????18??????????????,????????????12306??,?18????8??,??????1.75??????,???18?2??1??????,??????

????????:????????????“???????????????”???

????????,????,??“???????”??“?”???????????,???????????????“?”????????????,????

??????????,??????????????????????????????????????????????,??????,????????????????,?????????????????????“????”????????800??????????,??????????????????????600??

?????????????????????,????1200??????????????

???????????,?????????????????????????????????“??”“???????”???????????????,??????????65%?

16??C919????????????

??,???16???????????C919????????,?????C919?????

????,??10???C919??,??????????????3??C919????????????,?????????????????????????????????????5??????????????????????,??????400???????????????3??C919?????????????,???????????????????????4?????

???,??C919???????????????,???????,??????????,?????????

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