The network diagram shows a circuit with a 30V voltage source, resistors R1, R2, R3 connected in parallel. The problem asks to find the current I, voltage E, currents I1, I2, and equivalent resistance RT. The solution finds: I = 2.08A, E = 18V, I1 = 3A, I2 = 2A, RT = 3.6 ohms. It also finds that if R1 = 2R3 and R2 = 7R3, then the voltages across R1, R2, R3 are 6V, 21V, 3V respectively.