放射性物质无处不在。低浓度放射性对人体无害。但高浓度放射性绝对有害！氡能引起肺癌

来源: cowpi 于 2023-08-28 08:47:20 [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.