A construction company is preparing for a nine$-$month project and they need to develop a staffing plan. The number of workers required for the project by month is shown below:

Month $123456789$

Req FTE $152359657177644321$

The company can assign up to $30$ of its own full$-$time employees to the project, and will hire short$-$term contract employees to make up any shortage in meeting the personnel requirements. Company employees earn $$6,000$ per month and will get paid for all $9$ months. Contract employees can be assigned to the project beginning in any month, and their contract period is two months and they are paid $$8,600/$month for those months.

are All constraints in the staffing plan problem are binding?