2.6. Assuming a continuous signal is given as

x(t) = 10cos(27-5, 500t) + 5sin(27-7,500t), for t>0

sampled at a rate of 8,000 Hz,

a. sketch the spectrum of the sampled signal up to 20 kHz;

b. sketch the recovered analog signal spectrum if an ideal lowpass filter with a cutoff

frequency of 4 kHz is used to filter the sampled signal in order to recover the original signal;

c. determine the frequency/frequencies of aliasing noise.

explain magnitudes of the spectrum. show additional work on this.