In the circuit shown, the input $V_i$ is a sinusoidal AC voltage having an rms value of $230 \mathrm{~V} \pm 20 \%$. The worst case peak-inverse voltage seen across any diode is $\_\_\_\_$ V. (Round off to 2 decimal places)

A CMOS Schmitt-trigger inverter has a low output level of 0 V and a high output level of 5 V . It has input thresholds of 1.6 V and 2.4 V . The input capacitance and output resistance of the Schmitt trigger are negligible. The frequency of the oscillator shown in the figure is $\_\_\_\_$ Hz. (Round off to 2 decimal places)

The waveform shown in solid line is obtained by clipping a full-wave rectified sinusoid (shown dashed). The ratio of the rms value of the full-wave rectified waveform to the rms value of the clipped waveform is $\_\_\_\_$ . (Round off to 2 decimal places,)

$$ \text { For the closed-loop system shown, the transfer function } \frac{E(s)}{R(s)} \text { is } $$