Callum Communications runs a small call center that operates 7 days a week. Callum requires a specified minimum number of employees to be at work each day to provide the necessary level of customer service. Under union regulations, employees at the call center must all work full-time schedules, which means 5 consecutive workdays and 2 days off per week. Furthermore, employees whose regular schedules include a weekend day receive a pay premium. Specifically, employees who work 5 weekdays are paid $400 per week. Employees who work one of the weekend days are paid $440, and employees who work both of the weekend days are paid $470. The minimum daily requirements for workers are described in the following table. Day Sunday Monday Tuesday Wednesday Thursday Friday Saturday Requirement 16 18 18 17 15 8 5 Callum's management wishes to minimize the cost of salaries paid to the workforce while meeting the staffing requirements