The Beginning Inventory and Purchases of an Item for the Period

The beginning inventory and purchases of an item for the period were as follows:? $\begin{array}{ll}\text { Beginning inventory } & 6 \text { units at } \$ 70 \text { each } \\\text { First purchase } & 10 \text { units at } \$ 75 \text { each } \\\text { Second purchase } & 18 \text { units at } \$ 80 \text { each } \\\text { Third purchase } & 10 \text { units at } \$ 90 \text { each }\end{array}$ 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. Do not round your intermediate calculations. Round your final answer to two decimal places.