??????? ???????????15.3?
?????????????2????17? (????? ?????)?????????17???,???,2???????????13??16??,???????,????72??????????15.3?,????????????;?????10???48??6.5?~10.9??????????,??;????????????????????4??????????????
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??????????2?18????????????2??????22??,??,??????????,????2??19?2?????????????????20???,??,?????,???????????????????,?,?????????????????????(???????)
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