??????
??????
??????
??????
??????
??????
??????
??????
??????
??????
??????
??????
??????
??????
??????
??????
??????
??????
??????
??????
??????
??????
??????
??????
??
??:????“????BA” ?
??:????“????BA” ?
??
????:
1??????????????:?????????
2??????????
3???200??
4???????
5?????400????
????
6
%
???:??