I made Master of control of highly non-linear control system .To check my ability the question 1 part b is not stable so it has no overshoot
question 2 solution in this code run it in mfile to get your result .
%%% Function to plot family of curves for 1/(1+s)^2 %%%
close all,clear all,clc
n=4;
s=sym('s');
figure(1);
t=0:.01:16;
plot(t,.63),hold on
for i=1:n
x=(1+s)^i;
y=sym2poly(x);
z(i)=tf([1],y);
step(z(i)),hold on,grid on
legend('n=1','n=2','n=3','n=4')
pause(3)
end