?? ???????????????
????:1?????????:????
2?????????
3??????????????
4???????
5????
6????????????26??,??
???????190.65????,????????????????????8.75????????????????????,?????600??????????????????????????????,???,??P2??????????,???????????????????????????????????,????,?1400?????,??????
??????????????????????,????????????“2+3+N”?????????,??????????????????(????? ??? ????)
??????????????????:???