I need three spreadsheets with formulas and steps according to below instructions:

The Porter Company produces messenger bags. Porter must decide how many bags to produce each month. The company will use a $6-$month planning horizon. The forecasted monthly demands for the next six months are $10,000,15,000,30,000,35,000,25,000,$ and $10,000.$ Porter wants to meet these demands on time, knowing that it currently has $5000$ bags in inventory and that it can use a given months production to help meet the demand for that month. Assume that production occurs during the month, and demand occurs at the end of the month. During each month there is enough production capacity to produce up to $30,000$ bags, and there is enough storage capacity to store up to $10,000$ bags at the end of the month, after demand has occurred. The forecasted production costs per bag for the next six months are $$12\mathrm{.}50,$ $$12\mathrm{.}55,$ $$12\mathrm{.}70,$ $$12\mathrm{.}80,$ $$12\mathrm{.}85,$ and $$12\mathrm{.}95,$ respectively. The holding cost incurred per bag held in inventory at the end of any month is $5\%$ of the production cost for that month. $($This cost includes the cost of storage and also the cost of money tied up in inventory.$)$ The selling price for bags is not considered relevant to the production decision because Porter will satisfy all customer demand exactly when it occursat whatever the selling price is$.$ Therefore, Porter wants to determine the production schedule that minimizes the total production and holding costs.

$1.$ You are asked to develop a linear programming model to find the production schedule that meets demand on time and minimizes total production and inventory holding costs. Create a spreadsheet model to develop an optimal feasible solution of the production plan for the Porter Company.

Additionally, complete the following modifications:

$2.$ In one modification of the Porter problem, the maximum storage constraint and the holding cost are based on the average inventory $($not ending inventory$)$ for a given month, where the average inventory is defined as the sum of beginning inventory and ending inventory, divided by $2,$ and beginning inventory is before production or demand. Modify the model with this new assumption and use Solver to find the optimal solution

$3.$ Modify the original model in the following way. Assume that the timing of demand and production are such that only $90\%$ of the production in a given month can be used to satisfy the demand in that month. The other $10\%$ occurs too late in that month and must be carried as inventory to help satisfy demand in later months.

No need to write the algebraic models. Please submit a excel file that includes three different spreadsheet models and the optimal solutions for Q$1,$ Q$2,$ Q$3.$