A:he believed
B:who he believed
C:he believed she
D:whom he believed
如图,E为内阻不能忽略的电池,R1、R2、R3为定值电阻,S0、S为开关,V与A分别为电压表与电流表.初始时S0与S均闭合,现将S断开,则( )
下面加线字注音有误的一项是( )。