20. The output of first order system given by C(s)/ R(s) = 2/(s+4),the steady state error is C. 1 D. undefined B. 0.5 21 The following control action is seldom () used alone in practice:

20. The output of first order system given by C(s)/R(s)=2/(s+4), the steady state error is B. 0.5 C. 1 D. undefined