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

2?????????

3???????

4?????????

5??????????

?? ??2??????????????6?????18?:

??,?,2?6?????20????8??????????????20????????,??????????????????????6~8?,??????,????????????10???????;????4~6?,??????????7~8?,??10???8????????????????,??0????????????????,?????6~8??

????:

1??;

2????;

3??????????????????;

4?????

???????????????:???????