The following units of an inventory item were available for sale during the year. Beginning inventory 10 units at $55 First purchase 25 units at $60 Second purchase 30 units at $65 Third purchase 15 units at $70 The firm uses the periodic inventory system. During the year, 60 units of the item were sold. The ending inventory cost using LIFO is Oa. $1,150 Ob. $1,375 Oc. $1,250 Od. $1,350