[The following information applies to the questions displayed below.] The following information pertains to Mason Company for 2018: Beginning inventory Units purchased 90 units 280 units @ @ $20 $25 Ending inventory consisted of 40 units. Mason sold 330 units at $50 each. All purchases and sales were made with cash. Operating expenses amounted to $4100. Required a. Compute the gross margin for Mason Company using the following cost flow assumptions: (1) FIFO, (2) LIFO, and (3) weighted average. (Round "Cost per unit" to 2 decimal places and final answers to nearest whole dollar amount.) FIFO LIFO Weighted Average Gross margin