1. The problem statement, all variables and given/known data http://img463.imageshack.us/img463/997/screenshot01mu1.jpg [Broken] 2. Relevant equations V = IR Rseries = R1 + R2 + ... + Rn Rparallel = (1/R1 + 1/R2 + ... + 1/Rn)^-1 3. The attempt at a solution I simplified the circuit, to find I = 3mA. What I did was this (in order starting from far right): 6||3 = 2kohm, which is in series with 16kOhm, so 18kOhm. The 18kOhm is in || with 9kOhm, so 6kOhm. 6kOhm is in || with 6kOhm, so total of 12kOhm. The 12kOhm is in || with 4kOhm, as well as the 6kOhm. So I got 2kOhm for that part. Then, then 1kOhm and the 2kOhm are in series, so that equals 3kOhm total equivalent resistence. Then, I found that I = 3mA. Now, it says to find I_0. I have no clue as to how to do this. I think my simplifying is correct.