When prices are falling (deflation), which costing method would produce the highest gross margin for the following? Choose first-in, first-out (FIFO); last-in, first-out (LIFO); or average, if ABC Company had the following transactions for the month. Calculate the gross margin for each of the following cost allocation methods, assuming ABC Company sold just one unit of these goods for $400. Provide your calculations. (6 pts) A. first-in, first-out (FIFO) B. last-in, first-out (LIFO) C. average (AVG)