如图所以电路，电阻R 等 于 (     ) 。 

试卷相关题目

SQL Error: select id,body,options from ***_enewstiku_ where sourceid='69437' and id < 4496808 and id<>'4496808' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku_ where sourceid='69437' and id > 4496808 and id<>'4496808' order by id asc limit 5