Given the following information, determine the cost of goods sold at December 31 using the weighted-average perpetual inventory method. December 2: 5 units were purchased at $7 per unit. December 9: 10 units were purchased at $9.40 per unit. December 11: 12 units were sold at $35 per unit. December 15: 20 units were purchased at $10.15 per unit. December 22: 18 units were sold at $35 per unit.
| a)$282.30 |
|
$332.10 |
|
$281.25 |
 |
$290.70 |
|
$210.30 |