periodic inventory by three methods;cost of merchandise sold

The units of an item available for sale during the year were as follows:

Jan1. inventory 1,800 units at $108, Mar,10. purchases 2,240 units at $110,

Aug. 30 purchase 2,000 units at $116. Dec. 12 purchase 1,960 units at $120.

there are 2,000 units of the item in the physical inventory at december 31. the periodic inventory system is used.

Determine the inventory cost and the cost of merchandise sold by the methods.