b) Consider the following system describing a resonator : 1 -1 2 - 1-2r cos 0 z +r z -2 H(z)= Provide an approximate relation between r, and the frequency of the resonant peak in H(ejo) (in terms of the pole locations). c) Write a script to show the magnitude of the frequency response of the system. Use some values of r in the range 0.7 T freqz. Use a constant value of 0=- What happens to the magnitude of the peak and to 4 the bandwidth of the peak as r increases ? d) Using the impz function, find and plot the impulse response of the resonator when r=1, for a non-zero value of 0.