Some people have asked for clarification on Part I. D. It is asking you to compare theory to simulation using |Yb(f = 25 kHz)| as a basis. It can be done by looking at the ratios: |Yb(f = 27 kHz)| / |Yb(f = 25 kHz)| and |Yb(f = 30 kHz)| / |Yb(f = 25 kHz)| for both the theoretical case and the simulated case. Prof. LoCicero