?? ????????????
????:1??????????:??????????
2?????????
3?????vx
4???400??
5???????
??????????,??“????”??????????????????,????“??????”????,????,?“??????”????,???,«?????»«????»«????»???,????????????
??????????????????,??9????22????10?????7??,???????????????????????????“1+3+6+N”?,???????????????????????,???????????,??????????????
(???? ??????? ??? ? ??????????? ??)
????:??????????