Warren industries uses a process-costing system for its single product, which is manufactured from material x and material y. X and y are introduced to the product as follows: material x: added at the beginning of manufacturing material y: added at the 75% stage of completion the company started and completed 40,000 units during the period, and had an ending work-in-process inventory amounting to 8,000 units, 20% complete. Which of the following choices correctly expresses the total equivalent units of production for material x and material y?.