Fillipo, Inc., had $800$ units of inventory on hand at March $1,2006,$ costing $$20$ each. Purchases and sales of inventory during the month of March were as follows:

$\backslash$table$[[$Date$,$Purchases,Sales$],[$March $8,,600$ units$],[15,400$ units @ $$22$ each,$],[22,400$ units @ $$24$ each,$],[27,,400$ units$]]$

Fillipo uses the periodic inventory system The cost of inventory at the end of March applying the average method is: i need a detailed answer with steps please