The transfer function of a linear time invariant system is given by $$H\left(s\right)\;=\;2s^4\;-\;5s^3\;+\;5s\;-\;2$$. The number of zeros in the right half of the s-plane is __________.

A closed-loop control system is stable if the Nyquist plot of the corresponding open-loop transfer function

The output of the combinational circuit given below is

Identify the circuit below.