a- Use the properties of delta function to find the Fourier transform of i-x(t) = A cos(@ct) ii- y(t) = A sin(act) Then plot their magnitude and phase spectra assuming A=2 V and fe=10 kHz. b- Prove the results depicted in Fig. 4. 87(1) -T O (a) T 2T -0 030 2at (6) Fig. 4 Unit impulse train and its magnitude spectrum. (2-2)