4) Consider the LTI system T defined by 5 y[n] = x[n] + x[n 1] {x{n 2] where r[n] is the input signal, y[n] is the output signal, and h[n] is the impulse response. a) Find the magnitude response |H() for the system. b) Use MATLAB to plot |H(0)|. c) Find the poles and zeros of H(2). d) How many different possible sets of poles and zeros are there for causal LTI systems with this magnitude response |H(N)|? e) Find the possible sets of poles and zeros for causal LTI systems with magnitude response |H(2)|. f) Find the poles and zeros for the minimum-phase system with magnitude response |H()|.