The open-loop transfer function of the system shown in the figure, is

$$ G(s)=\frac{K s(s+2)}{(s+5)(s+7)} $$

For $K \geq 0$, which of the following real axis point(s) is/are on the rool locus?

$$ \text { Let } G(s)=\frac{1}{(s+1)(s+2)} \text {. Then the closed-loop system shown in the figure below, is } $$

Consider the state-space model $$ \begin{aligned} \dot{x}(t) & =A x(t)+B u(t) \\ y(t) & =C x(t) \end{aligned} $$ where $x(t), r(t), y(t)$ are the state, input and output, respectively. The matrices $A, B, C$ are given below $$ A=\left[\begin{array}{cc} 0 & 1 \\ -2 & -3 \end{array}\right], B=\left[\begin{array}{l} 0 \\ 1 \end{array}\right], C=\left[\begin{array}{ll} 1 & 0 \end{array}\right] $$ The sum of the magnitudes of the poles is ___________. (Round off to nearest integer)

A controller $D(s)$ of the form $\left(1+K_D s\right)$ is to be designed for the plant $G(s)=\frac{1000 \sqrt{2}}{s(s+10)^2}$ as shown in the figure. The value of $K_D$ that yields a phase margin of $45^{\circ}$ at the gain cross-over frequency of $10 \mathrm{rad} / \mathrm{sec}$ is _________(round off to one decimal place).