????:1?????:????KB?

2????????????

3???????

4???????

5?????

?????????6???????????20???????????????? ??????????????:????19??

????19?????????,??,??15?????17????????,??????????????

??,??????????18????????41???,?95%?????????????????????,?????,??????,“????”?

?????,?1800?????????????????,???????????

?,???????????75%????????????????,?,??????,??????,????????????4?19???????????,????60?????????????????????????(?????????) ??????????????:??????????