a) Devop an aggregate plan that uses a level workforce. Inventory build up and backorders are allowed.

b) Develop an aggregate plan that does not allow for invetory to build up. Hire and fire workers as approriate to meeet demand.

c) Develop an aggregate plan that uses a stable workforce, but can increase or decrease by no more than one worker when needed.

\begin{tabular}{|c|c|c|c|c|c|c|c|c|} \hline Begin Inventory & 0 & & Costs & & & & & \\ \hline Current workers & 38 & & Inventory carrying cost/unit & $25 & & & & \\ \hline \multirow{4}{*}{ Production/worker } & 10 & & Hiring \& Training & $200 & & & & \\ \hline & & & Firering/layoff & $300 & & & & \\ \hline & & & Backorder cost/unit & $100 & & & & \\ \hline & April & May & June & July & August & September & Total & \\ \hline Demand Forecast & 420 & 360 & 390 & 350 & 420 & 340 & 2,280 & \\ \hline Beginning Inventory & 0 & 0 & 20 & 10 & 40 & 0 & & \\ \hline Net production required & 420 & 360 & 370 & 340 & 380 & 340 & & \\ \hline Workers required & 42 & 36 & 37 & 34 & 38 & 34 & & \\ \hline Hired/availabe & 38 & 38 & 38 & 38 & 38 & 38 & & \\ \hline Laid off & 0 & 0 & 0 & 0 & 0 & 0 & & \\ \hline Actual Production & 380 & 380 & 380 & 380 & 380 & 380 & & \\ \hline Ending Inventory & -40 & 20 & 10 & 40 & 0 & 40 & & \\ \hline \multicolumn{9}{|l|}{ Costs } \\ \hline \multicolumn{9}{|l|}{ Labor } \\ \hline Inventory & 0 & 500 & 250 & 1000 & 0 & 1000 & 2,750 & \\ \hline Backorders & 4000 & 0 & 0 & 0 & 0 & 0 & 4,000 & \\ \hline \multicolumn{9}{|l|}{ Hiring } \\ \hline Layoff & & & & & & & & $6,750.00 \\ \hline \end{tabular} \begin{tabular}{|c|c|c|c|c|c|c|c|c|} \hline Begin Inventory & 0 & & Costs & & & & & \\ \hline Current workers & 38 & & Inventory carrying cost/unit & $25 & & & & \\ \hline \multirow{4}{*}{ Production/worker } & 10 & & Hiring \& Training & $200 & & & & \\ \hline & & & Firering/layoff & $300 & & & & \\ \hline & & & Backorder cost/unit & $100 & & & & \\ \hline & April & May & June & July & August & September & Total & \\ \hline Demand Forecast & 420 & 360 & 390 & 350 & 420 & 340 & 2,280 & \\ \hline Beginning Inventory & 0 & 0 & 20 & 10 & 40 & 0 & & \\ \hline Net production required & 420 & 360 & 370 & 340 & 380 & 340 & & \\ \hline Workers required & 42 & 36 & 37 & 34 & 38 & 34 & & \\ \hline Hired/availabe & 38 & 38 & 38 & 38 & 38 & 38 & & \\ \hline Laid off & 0 & 0 & 0 & 0 & 0 & 0 & & \\ \hline Actual Production & 380 & 380 & 380 & 380 & 380 & 380 & & \\ \hline Ending Inventory & -40 & 20 & 10 & 40 & 0 & 40 & & \\ \hline \multicolumn{9}{|l|}{ Costs } \\ \hline \multicolumn{9}{|l|}{ Labor } \\ \hline Inventory & 0 & 500 & 250 & 1000 & 0 & 1000 & 2,750 & \\ \hline Backorders & 4000 & 0 & 0 & 0 & 0 & 0 & 4,000 & \\ \hline \multicolumn{9}{|l|}{ Hiring } \\ \hline Layoff & & & & & & & & $6,750.00 \\ \hline \end{tabular}