Hello friends, I have problems in simplifying electrical circuits. I've attached 2 (of the many) questions I have trouble with. According to the question, superposition must be used to solve these. In the first question, supposing the voltage source doesn't exist, how do you simplify the left hand side of the circuit with the 3 6k resistors and the 2mA source? Can I combine the 6k resistor in the middle with the one on the left because they share a common ground node? In the second one, I know one node of the 3k resistor, 6k resistor and 2mA source on the left hand side can be connected to ground (suppose the voltage source there doesn't exist or is short-circuited), and the other node shared by all 3 so they can be put in parallel. But does the 2mA source flow from the upwards direction or the downwards direction? How do you determine that? It looks confusing to me. These aren't homework questions but just practice questions I'm doing for my final exam soon. I feel like if I understand these concepts better I would have no problems solving these questions.