Consider a four$-$month sales and operations planning problem with the monthly demand data shown below. For questions $1,2$ and $3$ :

$($i$)$ each employee makes $5$ units per month,

$($ii$)$ each plan should start and end with $10$ employees,

$($iii$)$ each plan should start with $20$ units of inventory $($at the end of April$=$beginning of May$),$

$($iv$)$ each employee hired costs $$400$ and each employee laid off $($fired$)$ costs $$600,$

$($v$)$ the inventory holding cost is $$100$ for each unit each month, and

$($vi$)$ the production cost is $$200$ per unit and the selling price is $$350$ per unit.

Total Profit $=$

level plan?

Number of Employees needed each month $=$

Total Profit $=$