?? ?????????????????:???
????:1????????????:????????????
2??????
3????????
4????????vx
5???sn??
????????????????????1?????????????????????8?????(??????????? ?? ??????)??1??????????????????????8??????????????
?????????????:???????????,????????????,????,???“??+???”“????+?????”?????“?”???????
??:????,???????????:??????10??,??5000??????????????????,??????????,??????????,?????,??????,“???????????????????”????????????????
???????????“???????????????????????”???????????????,?????????“????”????,?????????15????,??????????,?????????????????????,?????????????????????????????????????,????????????,?????????????????????(?) ???????:???