A differential amplifier is shown below. The MOSFET parameters are listed beside the circuit. N-channel MOSFET parameters Kn = 4×10−5 Vt = 1.5 V VA = 50 V P-channel MOSFET parameters Kp = 4×10.5 Vt = 1.5 V VA = 25 V a) Vsig = 0.01 sin(2π×103 t). What is the output voltage V0(t). b) What is the value of Rref ?