1. (14 Points) Given the following difference equation, determine the transfer function (H(z)), plot the frequency response (i.e., magnitude and phase responses) using freqz with a normalized frequency axis, and the z-plane plot (using either the band a coefficients or the poles and zeros). Indicate if the system is stable or not using the 2-plane plot. Show all your work and provide your Matlab code to receive full credit. y[n] = x[n] + 0.6x[n - 1] +0.03x[n -2] + 1.5y[n - 1] -0.6yn - 21