Beginning inventory, purchases, and sales for Item Zeta9 are as follows:

Oct.1Inventory43 units @ $25
7Sale 31units
15Purchase28 units @ $28
24Sale 21units
Assuming a perpetual inventory system and using the first-in, first-out (FIFO) method, determine
(a) the cost of goods sold on October 24
(b) the inventory on October 31.