1. If $Z_1 = (10 - j15)$, $Z_2 = (15 + j10)$, $Z_3 = (5 - j10)$, $Z_4 = (15 + j5)$, $Z_5 = (15 - j10)$, $Z_6 = (10 - j5)$, $Z_7 = (10 + j15)$, $Z_8 = (15 - j5)$, $Z_9 = (5 + j15)$, $Z_{10} = (5 + j10)$, and $Z_{11} = (15 + j5)$, determine $I_A$, $I_B$, and $I_C$.
2. Three equal impedances of $(8 + j6)$ ohms are connected across a 3-phase supply. The phase voltages are $V_a = (220 + j0)$, $V_b = (-j220)$, and $V_c = (-100 + j220)$ V. Calculate the symmetrical components of the voltages and currents.
3. Given the circuit below. Using 20kVbase and $S_{base} = 100MVA$ in the generator circuit, compute and draw p.u. equivalent circuit.