19. The following are information about purchases and sales for main product of AMEER Inc. for year 2020: ((Beginning inventory)): 9,000 units / $4 each ((Purchases)): - February: 21,000 units / $6 each -June: 30,000 units / $8 each ((Sales)): - March: 20,000 units. - November: 30,000 units. AMEER uses the "Weighted Average method". Required: If you know that AMEER uses the ((perpetual inventory system)), compute the "weighted average cost per unit" on June 30.