Need help with this question...

The following information relates to Ivanhoe Ltd.'s inventory transactions during the month of October. All of the units sold on October 5 were priced at $25 per unit. All of the units sold on October 15 and 31 were priced at $35 per unit. Ivanhoe Ltd. uses the perpetual inventory system. Calculate Ivanhoe' cost of goods sold, gross margin, and ending inventory for the month of October using weighted-average. (Round calculations for cost per unit to 2 decimal places, e.g. 10.52 and final answers to 0 decimal places, e.g. 61,052.) Cost of goods sold $ Gross margin $ Ending inventory $