In a purely resistive circuit, the voltage and current are in phase, resulting in a phase difference of 0 degrees.

The formula for equivalent capacitance in series is 1/C_eq = 1/C1 + 1/C2. Thus, 1/C_eq = 1/6 + 1/3 = 1/2, so C_eq = 2μF.

Norton current I_N = V / R = 12V / 4Ω = 3 A.

The voltage across the 5Ω resistor is half of the total voltage due to the voltage divider rule: V_th = 10V * (5Ω / (5Ω + 10Ω)) = 10V * (1/3) = 3.33V.

Total resistance R = 8Ω + 4Ω = 12Ω. Using Ohm's Law, I = V / R = 24V / 12Ω = 2 A.