The NMOS transistor in the circuit of Fig. 4 has Vt = 0.5 V, μnCoxW/L

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The NMOS transistor in the circuit of Fig. 4 has Vt = 0.5 V, μnCoxW/L = 2 mA/V2, and VA = 30 V. (a) Neglecting the dc current in the feedback network and the effect of ro, find VGS. Then find the dc current IF in the feedback network to verify that you were justified in neglecting the current in the feedback network. (b)Evaluate the gm value using the VGS found in (a). Then, find the small-signal voltage gain, vo/vsig, of this circuit without neglecting the effects of ro and the feedback network. Fig. 4

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(20 points) The NMOS transistor in the circuit of Fig. 4 has $V_{t} = 0.5 V, μ_{n} C_{α x} W / L$ $= 2 m A / V^{2}$ , and $V_{A} = 30 V$ .
(a) Neglecting the dc current in the feedback network and the effect of $r_{o}$ , find $V_{G S}$ . Then find the dc current $I_{F}$ in the feedback network to verify that you were justified in neglecting the current in the feedback network.
(b)Evaluate the $g_{m}$ value using the $V_{G S}$ found in (a). Then, find the small-signal voltage gain, $v_{o} / v_{s i g}$ , of this circuit without neglecting the effects of $r_{o}$ and the feedback network.
Fig. 4