please solve it without assuming any data

Problem 3 A local canning company sells canned vegetables to a supermarket chain in the Chicago area. A typical case of canned vegetables requires an average of 0.2. day of labor to produce. The aggregate inventory on-hand at the end of June is 800 cases. The demand for the vegetables can be accurately predicted for about 18 months based on the orders received by the firm. The predicted demands for the next 18 months are: The firm currently has 25 workers. The cost of hiring and training a new worker is $1,000 and, the cost to lay off one worker is $1,500. The firm estimates a cost of $2.80 to store a case of vegetables for a month. They would like to have 1,500 cases in inventory at the end of the 18-month planning horizon. Note, K (Units produced by one worker in one day ) = 0.225=5. a) Develop a spreadsheet to find the minimum constant workforce aggregate plan and determine the total cost of that plan. b) Develop a spreadsheet to find a plan that hires and fires workers monthly in order to minimize inventory costs. Determine the total cost of that plan as well. c) Graph the cumulative net demand and, using the graph, find a plan that changes the workforce level exactly once (not considering change in the workforce at the beginning of planning horizon, i.e., July) during the 18 months and has a lower cost than either of the plans considered in parts (a) and (b)