1. The problem statement, all variables and given/known data Which of the following circuits could be reduced to a single resistance and a battery by determining the equivalent resistance using combinations of resistors in series and parallel? A. II and IV only B. I and II only C. II and III only D. I and III only E. I and IV only 2. Relevant equations Parallel: 1/Req = 1/R1+1/R2+... Series: Req= R1+R2+.... 3. The attempt at a solution I think 3 and 4 can be eliminated because it seems impossible that you can reduce those to just one resistor. So I'm thinking the answer is I and II only, but I'm unsure.