GATE Electronics and Communications (EC) 2018 Solved Paper

The figure below shows the Bode magnitude and phase plots of a stable transfer function
$\mathit{G}\left(\mathit{s}\right)=\frac{{\mathit{n}}_0}{{\mathit{s}}^3+{\mathit{d}}_2{\mathit{s}}^2+{\mathit{d}}_1\mathit{s}+{\mathit{d}}_0}$

Consider the negative unity feedback configuration with gain in the feedforward path. The closed loop is stable for 𝑘 < 𝑘₀. The maximum value of 𝑘₀ is ______.