题目

如图所示,电源电压保持不变,开关S闭合后,灯L1、L2都能正常发光,甲、乙两个电表的示数之比是2:3.此时灯L1、L2的电阻之比是( ) A . 2:1 B . 3:2 C . 2:3 D . 1:2 答案:DThe village has developed a lot we________learned farming two years ago. A.when    B.which   C.that   D.where
科学 试题推荐