Suppose that a real sequence x[n] and its discrete-time Fourier transform (DTFT) X (ew) are known. The sampling frequency is fr. At normalized angular frequency we = /4 the DTFT X (e(/4)) = 1/2 + 3/2j. Determine the following: a) The absolute value |X (ej(/4))|. b) The complex angle X (e(/4)). c) The value of the DTFT for we = /4 using the fact that the sequence x[n] is real-valued. d) If fr 4000 Hz. what does we correspond to in Hertz? =