The ledger of American Company has the following work in process account. Work in Process-Painting 5/1 Balance 3,790 5/31 Transferred out ? 5/31 Materials 7,020 5/31 Labor 4,598 5/31 Overhead 1,980 5/31 Balance ? Production records show that there were 400 units in the beginning inventory, 30% complete, 1,700 units started, and 1,400 units transferred out. The beginning work in process had materials cost of $2,640 and conversion costs of $1,150. The units in 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