????:1??????:??????

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

3???sn??

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

5????????????

????2??5????????(??????????????????????? ??????????????)??5?,????????????????????,??????????????

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

??,???(??????????)????????????????,??????????????????????????,??????????????????????????????????,??,??????????????,????,?????????????,????????????????????

???????????8.3????,?????98.8???????????,??????2550????????????????????????????????????7260??????,???1130????????????(??????????) ??:??????