please explain the formuals you used to solve the problem

6. Complete the following MRP matrix for item A: Period Lot Size: 25 Item: A LT: 2 1 2 3 4 5 6 7 8 10 50 75 50 85 45 50 15 50 20 Gross requirements Scheduled receipts Projected on hand Net requirements Planned order receipts Planned order releases How many items are in inventory in periods 1.97 Ans: 20,60,45,20,20,10,0,5,20