BioHealth Corp. uses a periodic inventory system. The transactions for July are as follows:

Date	Activities	Units Acquired at Cost	Units Sold at Retail
Jul. 1	Beginning inventory	180 units @ $55 per unit
Jul. 5	Purchase	420 units @ $60 per unit
Jul. 12	Sales		400 units @ $90 per unit
Jul. 20	Purchase	280 units @ $65 per unit
Jul. 28	Sales		200 units @ $100 per unit

For specific identification, the July 12 sale consisted of 80 units from beginning inventory and 320 units from the July 5 purchase; the July 28 sale consisted of 150 units from the July 20 purchase and 50 units from the July 5 purchase.

Required:

1. Calculate the ending inventory value and COGS using specific identification and FIFO methods.
2. Determine the gross profit using the LIFO method.
3. Evaluate the impact of inventory costing methods on BioHealth Corp.'s cash flow and net income.
4. Recommend an inventory costing method considering BioHealth Corp.'s operational and financial objectives.