The signal flow diagram for a certain feedback control system is shown in figure
Now consider the following set of equations for the nodes
1. x₂ = a₁x₁ + a₉x₃
2. x₃ = a₂x₂ + a₈x₄
3. x₄ = a₃x₃ + a₅x₂
4. x₅= a₄x₄ + a₆x₂
Which of the following are correct?

In root locus analysis the breakaway and break in points

A. lie on the real axis

B. Either lie on the real axis or occur in complex conjugate pairs

C. Always occur in complex conjugate pairs

D. None of the above

Lag compensation permits a high gain at low frequencies.

A. True

B. False

The complicated shapes in the polar plots are only due to time constants in the numerator of transfer functions.

A. True

B. False

Which of the following features is not associated with Nichols chart?

A. (0 dB, -180°) point on Nichols chart represent critical Point (-1, 0)

B. It is symmetric about -180°

C. M loci are centred about (0 dB, -180°) point

D. The frequency at intersection of G (j$$\omega $$) locus and M = +3 dB locus gives bandwidth of closed loop system