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

2????????

3????????

4?????600?????

5???????

???(??????????????):6??????????????????17??30?????????,?????????,53%???????????

???,????????3.31?????????,?“??”????????????“????????????”???????????“??????????”???????4.8??????,??12.8???????????,????1978?????????5.05%?????13.84%??4?????????????,?????515????1000?????????,????,2019???????????????2000???????40%????????????????,?????????????,4.5??????????

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