2的倍數是雙數，5的倍數總是5，5只能與6相加成1。

来源: 南天北云于 2013-10-23 17:48:26 [博客] [旧帖] [给我悄悄话] 本文已被阅读：次

WENXUECITY.COM does not represent or guarantee the truthfulness, accuracy, or reliability of any of communications posted by other users.