please help! i know its a long question but they all have to go together! thank you

1) Folowing Inventory information below, What was the inventory at the end of March, 2020? In a company that produces sofas, the manager wants to prepare a plan for the next six months using the following information: ii. There are 5 workers, each making 30 sofas a month. iii. The maximum number of sofas produced during overtime is 30 per month. iv. Part-time workers can handle a maximum of 20 units per month. v. Beginning inventory is zero. 2) Develop a Initial Aggregate Plan, considering that costumers agree with Backorders: 3) Define the Backorder Cost in 6 months