i just need help with cost of goods sold columns and gross profit

Required information [The following information applies to the questions displayed below] Laker Company reported the following January purchases and sales data for its only product. The Company uses a perpetual inventory system. For specific identification, ending inventory consists of 385 units from the January 30 purchase, 5 units from the January 20 purchase, and 25 units from beginning inventory. Required: 1. Compute gross profit for the month of January for Laker Company for the four inventory methods using the periodic inventor system 2. Which method yields the highest gross profit? 3. Does gross profit using weighted average fall between that using FFO and LIFO? 4. If costs were rising instead of falling, which method would yield the highest gross profit? Complete this question by entering your answers in the tabs below. Compute gross profit for the month of January for Laker Company for the four inventory methods using the periodic inventory system. Note: Round cont per unit to 2 decimal places and final answers to the nearest whole dollars