kirtland corporation uses a periodic inventory system. at the end of the annual accounting period, december 31, the accounting records for the most popular item in inventory showed the following: transactions units unit cost beginning inventory, january 1 450 $4.00 transactions during the year: a. purchase, january 30 350 3.90 b. purchase, may 1 510 5.00 c. sale ($6 each) (210) d. sale ($6 each) (750) required: a. compute the amount of goods available for sale. b.