7. Assume that the prefilter is G s p( ) = 1. The proportional-plus-integral (PI) controller,

G s c ( ), that provides optimum coefficients of the characteristic equation for ITAE

(assuming ωn = 12 and a step input) is which of the following

a. Ge(s) = 72+ b. Ge(s) = 6.9 + c. Ge(s)=1+1 S 6.9 S 8-25 72 d. Ge(s) 14+10s