1. The problem statement, all variables and given/known data In the circuit as shown in Figure 4, there are three independent sources and five ordinary resistors. (a) Determine which of the circuit elements are sources and which are resistors? (b) Determine the value of the resistance for each of the resistors. http://img845.imageshack.us/img845/5295/unledvhg.png [Broken] 2. Relevant equations 3. The attempt at a solution Since every element can be reduced to an equivalent resistance, voltage, and branch current, it is impossible to tell whether any given element is a source or a resistor. My answer is wrong, and I couldn't find any similar questions or examples in my textbook to reference. The professor did not address this in class and I do not know where to start. EDIT: I only need help with part a. I did part b with no problem of course.