Second part for question: Produce a time array that goes from 0 to 0.25 in steps of 1/8000 seconds. Then create variables for the notes of a c major scale.

Regarding musical notes. Take the C note, E note and G note arrays and average them to produce a C major chord:

MATLAB code bellow:

% Define sample rate f_s

f_s = 8000;

% Create the time vector

time = 0 : 1/f_s : 0.25;

% Create a vector of the frequencies in the C Major scale

Frequencies = [523.2511 587.3295 659.2551 698.4565 783.9909 880.0000 987.7666 2*523.2511];

% Create a vector of the audio data

Tones = sin(2 * pi * time' * Frequencies);

% Create the scale by arranging each note in order, in a vector

Scale = Tones(:);

% Playing the sound at the sample rate f_s

sound(Scale, f_s);

Use the sound command to listen to the chord. In one figure plot the chord samples versus time in seconds both as a blue line and superimposed with red circles for each sample of the chord. Use the axis command to limit the time scale to 0 to 0.02 seconds. Include axis labels, a title, and grid lines, as shown below:

sin (2mfct) +sin (2mft) sin(2Tfct) chord(t) =