若线路上有人工作，应悬挂“禁止合闸，有人工作！”标示牌(   )。

试卷相关题目

SQL Error: select id,body,options from ***_enewstiku_ where sourceid='69530' and id < 4505080 and id<>'4505080' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku_ where sourceid='69530' and id > 4505080 and id<>'4505080' order by id asc limit 5