Problem $1\mathrm{.}1$

Consider a process with the following transfer functions for its primary and secondary elements,

$G_{p,\text{I}}=(\frac{1}{(0\mathrm{.}5s+1)(s+1)})$ and $G_{p,II}=(\frac{1}{0\mathrm{.}1s+1})$

The secondary process is faster than the primary, use the open$-$loop transfer with PI control $)=(1.$

Calculate:

Cross$-$over frequency and

ultimate gain for a simple feedback control and explain how you can also find the same values for a cascade control