. 2. Units to be assigned costs (8 pts.) Fortress Steel Company has two departments, Casting and Rolling. In the Rolling Department, ingots from the Casting Department are rolled into steel sheet. The Rolling Department received 4,000 tons from the Casting Department. During July, the Rolling Department completed 3,900 tons, including 200 tons of work in process on July 1. The ending work in process inventory on July 31 was 300 tons. How many tons were started and completed during July