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???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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