For given sample of salaries of four employees, the variance of their salaries is: 26 thousands of dollars
The formula for the variance is,

where,
= sample variance
= the value of the one observation
= the mean value of all observations
n = the number of observations
For given question,
n = 4
First we find the mean of their salaries.
(33 + 31 + 24 + 36 ) / 4 = 31
So, 
Using the formula for variance ,

Therefore, for given sample of salaries of four employees, the variance of their salaries is: 26 thousands of dollars
Learn more about the variance here:
brainly.com/question/13673183
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