6. Consider the feedback system in Figure 10.38, where

G(s) = 1000 s(s + 400)(s +20) A phase-lag compensator is designed for the system: 1+0.25s Ge(s) = 1+2s When compared with the uncompensated system (that is, G(s) = 1), the compensated system utilizing the phase-lag compensator: a. Increases the phase lag near the cross-over frequency. b. Increases the phase margin. c. Provides additional attenuation at higher frequencies. d. All of the above.