【单选题】如图, AB 两点间电压 U AB =______ 。 A . E 1 - E 2 - IR B . E 2 - E 1 - IR C . E 2 - E 1 + IR D . E 1 - E 2 + IR A. E 1 - E 2 - IR B. E 2 - E 1 - IR C. E 2 - E 1 + IR D. E 1 - E 2 + IR

基尔霍夫定律的公式表现形式为（ ）。 A: ΣI＝0 B: ΣU＝IR C: Σ＝IR D: Σ＝0 E: Σ＝1

电阻电感相并联，IR=3A，IL=4A，则总电流等于( )A。 A: 1 B: 5 C: 7 D: 8

Mother said to me:" I will wake you up at 7:00."Mother said that ______ ______ wake me up at 7:00.

A: (1)______ me!B: (2)______ ?A: (3)______ this (4)______ handbag?B: (5)______ ?A: Is this your(6)______ ?B: Let me (7)______ . Ah, (8)______ , it is.A: (9)______ you are.B: (10)______ you very much.

Question 7: Between you and I/me, this information is confidential. A: I B: me

Please ______ at 7 o’clock tomorrow morning. A: wake me B: wake up me C: wake me up

8. He left me a ____________ that he would meet me in the classroom at 7 P.M. (message)

由3个n选1的多路模拟开关构成一个3n选1的多路模拟开关，设断开开关的漏电流是IR，采用分层组合电路接法时，该模拟开关的总的漏电流是:() A: (3n-1)IR B: (n-1)IR C: (n1)IR D: (3n1)IR

已知RL并联电路，电阻电流IR=3A，电感电流IL=4A，则该电路的端电流为（ ）A。 A: 1 B: 3 C: 5 D: 7