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

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

3???app??

4????????

5???????

???????????????2???4? ???«????»??????????,????????????????????3?,??,??30??

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

?????????,?????????????????,???

?????????????,“????????????????30???,?????”

??????????????????,30?,??3?????????9?,???,?????????

?,?????????,????,??????????????45???????????????????????????????

????????????????????,???????????????????????,??????

????????????????????2????1?????,???,???25%???

????:??