Plot the original periodic square wave on the same graph

Question

Let

A = 250/I+100

and

T = 1/ 5I

For the expressions for a_n and b_n, use MATLAB to plot the function

for values of N = 5, 10, 20, for the time interval 0 ≤ t ≤ T. Plot the original periodic square wave on the same graph. Comment on the difference between the original periodic square wave and its truncated Fourier series presentation.