Problem $8-5($Algo$)$ Various inventory costing methods $[$LO$8-1,8-4]$

$[$The following information applies to the questions displayed below.$]$

A company began January with $4,000$ units of its principal product. The cost of each unit is $$6.$ Inventory transactions for the month of January are as follows:

$\backslash$table$[[,$Purchases$],[$Date of Purchase,Units,Unit Cost$*,$Total Cost$],[$January $10,3,000,$$$7,$$$21,000$