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28. Albert:_____________________Elissa:Oh, I see. I’ll add you later.(A) See you tomorrow. (B) Merry Christmas!(C) I just sent a friend request to you on Facebook. (D) I am full.

29. Anne:When will the football game start?Bill:In five minutes. ___________ We’re late.(A) Hurry up! (B) Time to go home.(C) Where? (D) It rains in summer.

30. Mark:Hi, Tony. What do you do to keep fit? Tony:____________________ Do you want to go with me? Mark:It sounds like a great idea!(A) It’s not your fault. (B) You are the painters.(C) I’m sure. (D) I swim seven times a week.

11. When the switch in the circuit is closed at $t = 0$, what is the time constant for the circuit to reach steady state? Each of the three resistors has resistance $R$, and each of the three capacitors has capacitance $C$. The internal resistance of the battery is negligible.(A) RC (B) 9RC (C) RC/9 (D) R/C(E) none of those answers

12. A particle with charge $q1 = -40.0 \, \text{nC}$ is located on the x-axis at $x = 0.0$. A second particle, with charge $q2 = -20.0 \, \text{nC}$, is located on the x axis at $x = 0.5 \, \text{m}$. Is there a point at a finite distance where the electric potential due to these two charges is zero? (A) Yes; it is to the left of $x = 0.0$ along x axis. (B) Yes; it is between $x = 0.0$ and $x = 0.5 \, \text{m}$ along x axis. (C) Yes; it is to the right of $x = 0.5 \, \text{m}$ along x axis. (D) Yes; but not along the x axis (E) No.

13. A parallel-plate capacitor is charged and then disconnected from the battery. The plate separation is then reduced to half its original value. By what factor does the stored energy in the capacitor change? (A) It remains the same. (B) It is doubled. (C) It decreases by a factor of 2. (D) It increases by a factor of 4. (E) It decreases by a factor of 4