Human Resources Management II: Data are available for a random sample of $80$ employees from Harris Bank Chicago. The HR Director wishes to build a model to explain gross monthly salary $($in dollars$)($SALARY$)$ as a factor of each employee's education level $($in years$)($EDUC$),$ previous work experience in the banking industry $($in months$)($EXPER$),$ and seniority$*($in months$)($TIME$),$ which is the number of months since the individual was hired.

$*$Seniority is the length of time that an individual has served in a job or worked for an organization. Seniority can bring higher status, rank, or precedence to an employee who has served for a longer period of time.