题目

在如图所示的电路中,电源两端的电压保持不变,当开关、都闭合时,电压表、的示数之比为5:3;当开关闭合、断开时,电阻与消耗的电功率之比为3:2。则下列判断中正确的是A.电阻阻值之比为3:2B.电阻阻值之比为5:3C.当开关闭合、断开时,电阻、消耗的电功率之比为1:1D.当开关闭合、断开时,电压表、的示数之比为3:2. The education system was once the ______of the country, but now it seems to be________.A.proud…in ruin B.pride…in ruins C.remains…falling into ruin D.wonder…fall into ruins
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