1. The problem statement, all variables and given/known data Write the loop rule for each of the following circuits: 2. Relevant equations Depending on the loop: -emf + IR1 + IR2 + .... + IRn = 0 V = IR If in series: R1 + R2 + ... Rn = R If in parallel: 1/R1 + 1/R2 + ... 1/Rn = 1/R 3. The attempt at a solution I really don't know how to do these because we usually only had 1 battery. But here's my shot: (A) Could you say that both batteries are in series and treat them as one battery, then say the R2 and R3 are in parallel? (B) and (C) I don't have the slightest clue. For (B), I don't know if you can say that R1, R2, and R3 are in series with emf3 there, and (C) we've never had a battery in parallel (We either had 1 battery or 2 batteries in series).