solve using excel. $2.$ Suppose that Ivar Jorgenson, a head operations planner for Bi$-$Product Company, finds out that the long$-$range forecast was revised by the growing economy. As a result, the marketing department at Bi$-$Product Company raises its forecast for quarter $2,3$ and $4$ sales of Product B to $7000,6500$ and $7000$ units respectively. He will now have to develop and analyze several alternative level plans for next year. Keep in mind that each of these plans must consider: $-$ Beginning inventory of $1,000$ units of Product A and $500$ units of Product B$.-$ Ending inventory and back orders for quarter $4$ must be zero $-$ Each plan must have the same level total$-$output rate each quarter. a$.$ Develop a level plan that uses overtime by regular, full$-$time employees to meet the new demand conditions $($with no additional hiring$).$ Calculate the total annual cost of this plan. b$.$ Develop a second plan that will use regular employees $($no overtime$)$ plus subcontracting to meet the new demand conditions $($with no additional hiring$).$ Calculate the total annual costs. c$.$ Another possibility would be to hire additional full$-$time employees on January and employ him$/$her for the full year. Calculate the total annual cost. $($overtime$,$ subcontract and part$-$time are not allowed$)$ d$.$ What would you suggest to Ivar Jorgenson for the best plan? Why?