Perpetual Inventory Using LIFO

Beginning inventory, purchases, and sales for Item PK$95$ are as follows:

$\backslash$table$[[$July $1,$Inventory,$110$ units @ $$35],[5,$Sale,$88$ units$],[11,$Purchase,$122$ units @ $$39],[21,$Sale,$102$ units$]]$

a$.$ Cost of merchandise sold on July $21$

b$.$ Inventory on July $31$