Consider the control system closed-loop represented such a block diagram below:

Given that: and

a) Determine the values of which the closed-system loop is stable.

b) Suppose that the disturbance be sinusoidal with amplitude A and frequency . The exactly value of is unknown, but know itself rad/s

Is it possible to choose a value of such that, in steady state, the amplitude of the output value is less than or equal to 1% of the value A?

**If your answer is “YES”, so compute the value of that guarantees this attenuation.**

**If your answer is “NO”, so show that there is no value of that guarantees this attenuation**.

However my question is very similar, i have some doubts about the letter b)

Is this correct?