how many units are in process in May?

The ledger of American Company has the following work in process account WORK IN PROCESS MANUFACTURING COSTS Raw Materials Factory Manufacturing Inventory Labor Overhead FINISHED GOODS INVENTORY -$5,670 Painting $3,790 5,670 4,104 1,680 -? Balance May 1 Materials Labor Overhead Transfer out Balance May 31 -$4,104 -$1,680 ? $? Production records show that there were 500 units in the beginning inventory, 30% complete, 1,800 units started and 1,500 units transferred out. The beginning work in process had materials cost of $2,840 and conversion costs of $950. The unitsin ending inventory were 40% complete. Materials are entered at the beginning of the painting process. How many units are in process at May 31? Work in process, May 31 units