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

2?????vx

3?????????

4?????????

5???????

???????1???9?? (?? ??)??1?9???????????

? ?? ???????????????

???????????????:??????????????????????????,?13??????????????????????

?:???????????????????????????????,????????????,???????????????????????

???????????,?????1????????7??????????????????,????????????,???????1????????13?????15???????? (??)

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