Question $1($a$)$

Do not ignore channel length modulation

What is the low frequency small signal gain $\frac{v_{\text{o}\text{u}\text{t}}}{v}i{n}_{in}?$

What is the low frequency small signal gain from the power supply VDD to the output $V_{\text{o}\text{u}\text{t}}?$

Question $1($b$)$

Ignore channel length modulation M$2=$M$3$

All transistors are in saturation

What is the low frequency small signal gain vout