采用间接验电时，至少应有（  ）的指示，且所有这些确定的指示均已同时发生对应变化，才能确认该设备已无电。 

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SQL Error: select id,body,options from ***_enewstiku_ where sourceid='69486' and id < 4500758 and id<>'4500758' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku_ where sourceid='69486' and id > 4500758 and id<>'4500758' order by id asc limit 5