The transfer functions of three different second-order low-pass filter design approaches shown in Figure P14-13 are as follows:

\[
\begin{aligned}
& T_{\mathrm{a}}(s)=\frac{1}{R_{1} R_{2} C_{1} C_{2} s^{2}+R_{2} C_{2} s+1} \\
& T_{\mathrm{b}}(s)=\frac{\mu}{R_{1} R_{2} C_{1} C_{2} s^{2}+\left(R_{1} C_{1}+R_{1} C_{2}+R_{2} C_{2}-\mu R_{1} C_{1}ight) s+1} \\
& T_{\mathrm{c}}(s)=\frac{-R_{2} / R_{1}}{R_{2} R_{3} C_{1} C_{2} s^{2}+\left[R_{3} C_{2}+R_{2} C_{2}\left(1+R_{3} / R_{1}ight)ight] s+1}
\end{aligned}
\]

The filter specifications are a cutoff frequency of \(100 \mathrm{krad} / \mathrm{s}\) and a \(\zeta\) of 0.2. Using Multisim, build your three designs and select the best one based on how well each meets the specs, the number of parts, and the gain.