$9\mathrm{.}29($a$)$ Find the VTC of the circuit of Fig. P$9\mathrm{.}29.($b$)$ Assuming $+-V_{\text{s}\text{a}\text{t}}=+-13V$ and $V_{D(on)}=0\mathrm{.}7$ V $,$ show all node voltages for $v_{\text{I}}=+3V$ and $v_l=-5V.($c$)$ List advantages and disadvantages of this circuit.