.用电压表测得电路端电压为零，这说明（   ）。

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SQL Error: select id,body,options from ***_enewstiku_ where sourceid='69505' and id < 4502657 and id<>'4502657' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku_ where sourceid='69505' and id > 4502657 and id<>'4502657' order by id asc limit 5