Crane Distribution markets CDs of numerous performing artists. At the beginning of March, Crane had in beginning inventory $2,800$ CDs with a unit cost of $$7\mathrm{.}00.$ During March, Crane made the following purchases of CDs$.$

$\backslash$table$[[$March $5,2,200,$@$,$$$8\mathrm{.}00,$March $21,5,000,$@$,$$$10\mathrm{.}00$

Please help me understand what LIFO and Average cost is