a plant has a transfer function shown below: G

$($

s

$)$

$=$

$1$

$/$

s

$($

s

$+$

$1$

$)$

$.$

$$a

$)$

$$determine the stability of the plant. b

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$$A feedback H

$($

s

$)$

$=$

$$K

$/$

$2$

s

$+$

$1$

$$is added to change the preformance of the system, determine the range of K so that the closed system is stable