1- Given an audio signal x(n) which is sampled by the sampling frequency of 10khz, x(n) is then subsampled with a M=5, what is the equivalent sampling frequency?

a. 2khz

b. 5khz

c. 3khz

d. 4khz

2- Given a sampled audio signal x(n) with a file size of 10MB we want to reduce the size to 5MB by using subsampling. What is the value of M for subsampling?

a. 2

b. 1

c. 3

d. 4

3- In frequency domain, given input X(f) and a filter H(f), how to calculate the output Y(f) = ___

a. Y(f) = X(f)*H(f)

b. Y(f) = X(f)+H(f)

c. Y(f) = X(f) - H(f)

d. Y(f) = X(f)/H(f)

4- Given a 2-bit A/D converter which has a full scale input range of 0 to +2V. What is the max quantization error in the voltage?

a. 0.5

b. 0.75

c. 0.25

d. 1