ID: A me: 3. List the internal control objectives illustrated by the following: (a) keeping the inventory storeroom locked (b) counting the inventory at the end of the accounting period and comparing it with the inventory ledger clerk's records (c) using subsidiary Tedgers and a perpetuar inventory system 4. The beginning inventory and purchases of an item for the period were as follows: Beginning inventory First purchase Second purchase Third purchase 6 units at $70 each 10 units at $75 each 18 units at $80 each 10 units at $85 each The company uses the periodic system, and there were 15 units in the inventory at the end of the period. Determine the cost of the 15 units in the inventory by each of the following methods, presenting details of your computations: (a) first-in, first-out, (b) last-in, first-out; (c) average cost