Wittmann Co. began operations on July 1. It uses a perpetual inventory system. During July, the company had the following purchases and sales. Purchases Date Units Unit Cost Sales Units July 1 5 $122 July 6 3 July 11 7 $136 July 14 5 July 21 8 $147 July 27 5 Instructions (a) Determine the ending inventory under a perpetual inventory system using (1) FIFO, (2) moving-average cost, and (3) LIFO. (b) Which costing method produces the highest ending inventory valuation?