钴-60的半衰期为

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SQL Error: select id,body,options from ***_enewstiku where sourceid='30100' and id < 2436852 and id<>'2436852' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku where sourceid='30100' and id > 2436852 and id<>'2436852' order by id asc limit 5