The message signal m(t), whose frequency spectrum is shown in the following figure. m(t) is the input of the given block diagram where y, (t) = x(t) + x (t). The bandpass filter has a bandwidth of 2W centered at 2fo- cos (4rfot) m(t) x(t) y2(1) Bandpass y3(1) Nonlinear Lowpass f Iter + device filter cos (2nfot) M(f)4 -W W a) Plot the frequency spectrum of the signals x(t), y1(t), y2(t) and y3(t). b) Determine the bandwidths of the signals x(t), y1(t), y2(t) and y3(t). c) Determine the cut-off frequency and amplitude of ideal low-pass filter to show m(t) signal at the output of the block diagram.