Exercise 5-19 effect of inventory cost flow (fifo, lifo, and weighted average) on gross margin lo 5-6 [the following information applies to the questions displayed below.] the following information pertains to mason company for 2018: beginning inventory 150 units @ $ 70 units purchased 410 units @ $ 73 ending inventory consisted of 100 units. mason sold 460 units at $146 each. all purchases and sales were made with cash. operating expenses amounted to $2700. rev: 09_05_2017_qc_cs-97527 exercise 5-19 part a required compute the gross margin for mason company using the following cost flow assumptions: (1) fifo, (2) lifo, and (3) weighted average.