Periodic System-Computing Cost of Sales and Gross Profit under FIFO and LIFO March 31 shcwed 90 untts available in invente y. Va lex Lses the perindic invertery system a. Compute cost uf goods sald and ending inventory for the lirst quarter of the year using (1) FFO ane :2) (1FO. - Note: Do not ase any negative signs with your ausivers. - Note: Do not ulse any Hega.ve signs with your answers. Periodic System-Computing Cost of Sales and Gross Profit under FIFO and LIFO March 31 shcwed 90 untts available in invente y. Va lex Lses the perindic invertery system a. Compute cost uf goods sald and ending inventory for the lirst quarter of the year using (1) FFO ane :2) (1FO. - Note: Do not ase any negative signs with your ausivers. - Note: Do not ulse any Hega.ve signs with your answers