Read the watchdog.wav file in matlab. a. Find out the sampling frequency of the sound file. b. Play the sound with different sampling frequencies. Discuss how the voice changes. c. Calculate the RMS of the sound signal in decibels (dB). d. Generate a Gaussian noise with mean = 0; std = 1; and plot the histogram of noise. e. Regenerate a Gaussian noise so that the SNR is 12dB. f. Add noise to the original signal and plot the new signal watchdog_new.wav.