Problem II $(10$ Points$)$

The US$-$Haul Truck Rental firm has accumulated extra trucks at three of its truck leasing outlets, as shown:

Each plant demands the following tons of potatoes per month:

The firm wants to transfer trucks from the outlets with extras to those with shortages at the minimum total cost. The following costs of transporting these trucks from city to city have been determined:

Formulate a linear optimization model that allows to determine how many extra trucks from each source should be dispatched to the which destination while minimizing the total cost of transportation. The model should clearly indicate the decision variables, objective function, and constraints.