ok, thanks for the reply, to my last question. Here is another one, which I can't figure out. Here is the situation a circuit consist of the following: 18 volt source, the circuit is a series-parallel set up like this: voltage source to r1 at 2 ohms, r2 at 2 ohms then the circuit turns to a parallel circuit r3 at 4 ohms r4 at 4 ohms then back to series with r4 at 2 ohms. Here is the question what is the volt meter reading between r3? I looked up the answer in the book and they have 1.5 volts, also they have 0.75 amps for this circuit, I just can't figure out how they came up with 0.75 amps. If I did this right the total resistance for this circuit should be about 8 ohms, but then again what do I know. any help would be appreciated