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

2?????

3?????sn

4???????

5?????

??????8?????????????13???? (?? ??????????)???????13?????????,??????,???????7???36%?

???????,?????????,???????7??,??????11.34?????????????????,????????36%,???????????????????????????????

?????,?????????????7??,??????,???????1.24???????,???75%,????????????????????????????;??(???????),????????3.22???,????64%,??????

????????????,???64%,?“?????”??????????????7????,?????????????????

???????,???????????????????????7???,???(??)???????2.16???,????????????154%,??????;?(???)?????????2.97???,??????????????57%,????????????(???) ????????:?????????????