10. Consider the feedback system in Figure 10.38, where

1 G(s) = = s(1+s/8)(1+s/20) The design specifications are: K, 100, G.M. 10 dB, P.M. 45, and the crossover frequency, we 10 rad/s. Which of the following controllers meets these specifications? (1+s)(1 + 20s) a. G(s) = b. G(s)= (1+s/0.01)(1 + s/50) 100(1+s)(1+s/5) (1+s/0.1)(1 + s/50) 1+100s c. G(s)= 1+120s d. G(s) = 100