6.66pts A company has the following: December 1 Beginning inventory of 15 units at $6.00 per unit December 7 Purchases 60 units at $6.75 per unit December 12 Sold 35 units December 20 Purchased 30 units at $7.75 per unit December 29 Sold 10 units Assuming that a perpetual inventory system is used, what is the cost of goods sold on a LIFO basis for December? What if a periodic inventory system had been used instead of perpetual? $333.75 using perpetual, and $423 using periodic $309.50 using perpetual, and $323 using periodic $292.5 using perpetual, and $313.75 using periodic $313.75 using perpetual, and $333.75 using periodic $333.75 using perpetual, and $313.75 using periodic