回复：2 ball questions

来源: yma16 于 2004-01-18 21:15:00 [] [旧帖] [给我悄悄话] 阅读数 : (51 bytes)
回答: 2 ball questions 由 yma16 于 2004-01-17 19:14:00

(1) is correct. (2) seems OK. Can you prove them?



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