影响变压器效率的因素有（   ）。

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SQL Error: select id,body,options from ***_enewstiku_ where sourceid='69323' and id < 4487965 and id<>'4487965' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku_ where sourceid='69323' and id > 4487965 and id<>'4487965' order by id asc limit 5