Hart Manufacturing makes three products. Each product requires manufacturing operations in three departments: A, B, and C.
The labor-hour requirements, by department, are as follows:

Department Product 1 Product 2 Product 3
A 1.95 3.45 2.45
B 2.90 1.90 3.40
C 0.70 0.70 0.70

During the next production period, the labor-hours available are 540 in department A, 440 in department B, and 140 in department C. The profit contributions per unit are $34 for product 1, $37 for product 2, and $39 for product 3.
Formulate a linear programming model for maximizing total profit contribution.