1) https://www.chegg.com/homework-help/questions-and-answers/2-given-control-system-shown-find-k-10-error-steady-state-r-s-e-s-c-s-k-s-5-s-s-6-s-7-s-8-q43435255

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3) https://www.chegg.com/homework-help/questions-and-answers/-hiz-hatas-n-n-0-06-ve-wn-12-olabilmesi-k-k-4-puan-b-sistemin-s-n-m-oran-ve-al-frekans-n-w-q56108781