Adjust for Different Slopes Using Interaction Terms in Multiple Regression

Adjust for different slopes using interaction terms in multiple regression.
-A sample of 30 companies was randomly selected for a study investigating what
Factors affect the size of company bonuses. Data were collected on the number of
Employees at the company and whether or not the employees were unionized (1 = yes,
0 = no) . The following multiple regression model was fit to the data. Based on this
Model, what is the annual average bonus for a company with 7500 employees that are not
Unionized? $$\begin{array}{l}\text { Dependent Variable is Average Annual Bonus }\\\\\begin{array} { l r r r r } \text { Predictor } & \text { Coef } & \text { SE Coef } & \text { T } & \text { P } \\\text { Constant } & - 1241.0 & 982.3 & - 1.26 & 0.218 \\\text { Employees } & 0.8872 & 0.1318 & 6.73 & 0.000 \\\text { Union } & 5253 & 1579 & 3.33 & 0.003 \\\text { Emp*Union } & - 0.05424 & 0.02012 & - 2.70 & 0.012\end{array}\end{array}$$

A) $5413
B) $10,259.20
C) $10,666
D) $5253
E) $7980.25