The Donaldson Company uses a job-order costing system. The following data were recorded for July: Added During July Direct labor $ 300 $ 900 $2,000 $2,000 Direct materials Job# 475 476 477 478 $500 $ 700 $1,000 $1,200 Overhead is applied to jobs at the rate of 80% of direct materials cost. Jobs 475, 477, and 478 were completed during July and transferred to finished goods. Jobs 475 and 478 have been delivered to the customer. Donaldson's Work in Process inventory balance on July 31 was: $7,280 $2,160 $3,160 $3,230 None of the above