Gibbons Company uses a process costing system and the weighted average method. The company had 410 units of product in its work in process inventory at the beginning of the period. During the period 1600 additional units of product were started. At the end of the period there were 800 units of product in the Work in Process account. The ending work in process inventory was estimated to be 40% complete The beginning work in process inventory had a cost of $2,500. Product costs totaling $43,000 were added to work in process during the period. The number of equivalent units in ending work in process is: Multiple Choice 640. To o o o 800. 1,280. 1,280. O 320