I added the plots in the attachments.
<u><em>Answer:</em></u>
The mean will decrease
The median will remain the same
<u><em>Explanation:</em></u>
<u>1- checking the mean:</u>
<u>Mean of the salaries is calculated as follows:</u>
<u>Now, we can note that two parameters affect the mean, let's consider each:</u>
<u>a. Number of employees:</u>
We are given that one employee is replaced with another. This means that the number of employees did not change
<u>b. Sum of salaries:</u>
We are given that a person earning $15 left and the new person earns $7. This means that:
New sum of salaries = old sum of salaries - 15 + 7 = old sum of salaries - 8
This means that the sum of salaries decreased by 8
<u>Now, for the mean:</u>
We can conclude that since the numerator decreased while the denominator stayed the same, the mean will decrease
<u>2- checking the median:</u>
In the whisker plots, the median is represented by the vertical line inside the plot.
<u>In the first plot,</u> we can note that the vertical line is nearly half the distance between 9 and 10. This means that, for the first plot, the median is approximately 9.5
<u>In the second plot,</u> the place of the median is unchanged. It is still approximately midway between 9 and 10 which means that the median in the second plot is approximately 9.5
Therefore, the median of the data remains unchanged.
Hope this helps :)