Download and load the file $$sum$.$mat$$ into MATLAB by placing it in your

MATLAB directory and running $$load sum;$$ The entries of the array sum are given as follows:

sum$[1]=$ z$[1]$

sum$[2]=$ z$[1]+$ z$[2]$

sum$[3]=$ z$[1]+$ z$[2]+$ z$[3]$

$.$

$.$

$.$

sum$[$N $1]=$ z$[1]+$ z$[2]++$ z$[$N $1]$

sum$[$N$]=$ z$[1]+$ z$[2]++$ z$[$N$]$

where z is an array containing an audio message. In other words, the kth entry of sum is the sum of

the first k entries of z$.$ Your goal is to use MATLAB to recover the audio message z from the array

sum and play it within MATLAB, using $$sound$($z$,$ Fs$)$;$$ where Fs $=11025.$ The array z has the same

length as the array sum.

$$ What is the $($well$-$known$)$ audio message? Include the code you used to decipher z$.$

$$ In MATLAB, let N $=$ length$($sum$)$; and define the array t $=(1$ : N$)/$Fs; Include the output of:

$$plot$($t$,$ z$)$;$$ and label:

$$ the x$-$axis as $$Time $($seconds$)$

$$ the y$-$axis as $$Amplitude$$

$$ the title as whatever you deem appropriate.

$$ When running $$sound$($z$,$ Fs$)$;$$ what happens if you set Fs $=5000,$ instead of $11025?$ What if

Fs $=20000?$