????:1????????py:????????

2?????vx

3???????v

4???????

5??????

???????2??????????????????12????????? (?????????? ??????????????)??????????????????,13??6???????????????,??????????????????????????????????,???????????

??????????????????????????,???????,??????????????????????????????????75.03?,????

????????????“??”???????????????????,???????????????????????62.90???????????????????,??????,????????????????,????,????,?????????????

??????????,???,??????????????????103.81??????????????,????,???????????????????????

???????????????????,???“??????????????????????”??????,???????????????????1:6?????????????????

???????????,???“????????????”???????????“??”?????????,?????????????????????12??2:1???????,????“????”?

13??????????,?????????????????????????????,????????????,?????????????

????????????,?????13?????????????????????????????,31??????U???

???????,?????????:“??,?????????????”

??????????????U???????????????????????,?,????????

???????????,???????4×6???????????????????????????4×7.5??????????????????,?????,???1????2???????

?????????7.5?“?”????????????????,?????????????????????????,???????????????????????,???????????(?????????????????) ???????????????:??????