1. (2 point) Piper Company had 8,500 units in ending inventory on December 31,2020. During 2020, the company's variable production costs were $4 per unit and its fixed manufacturing overhead rate was $8 per unit. If the company's operating income for 2020 was $13,920 higher under variable costing than it was under absorption costing, how many units were in beginning inventory on January 1, 2020? (Assume the company uses normal costing) a. 6,760 units b. 10,240 units c. 11,980 units d. 5,020 units e. 15,080 units f. 7,340units g. 9,660 units h. None of the above