Problem 6.2 (d) requires the use of the MATLAB functions:
pzmap
step
bode
You should now be developing the intuition to identify
how a system's step response, Bode plot and pole-zero locations
map to one another!
Again, note for 6.2(e) that only Kd should be revised
(with respect to the answer developed in parts (c) and (d).
Just use the same value of 'G' found in part (c).)