Final answer:
Ace Electronics' accountant should assume the cash register, purchased on January 11, was acquired on the midpoint of the year for depreciation. For the self-check question, the firm's accounting profit is $50,000, calculated by subtracting expenses from sales revenue.
Step-by-step explanation:
When calculating depreciation expense for the year ended December 31, Ace Electronics' accountant should assume that the cash register was purchased on the midpoint of the accounting period when using the half-year convention for depreciation expense.
This simplification is typical in accounting to avoid prorating the depreciation for assets purchased during the year. It assumes the asset was in service for half the year, simplifying the calculation of depreciation, particularly for tax purposes.
Regarding the self-check question, to calculate the firm's accounting profit, we subtract the total expenses from the sales revenue. The expenses include labor, capital, and materials. Hence, the calculation will be:
$1,000,000 (sales revenue) - $600,000 (labor) - $150,000 (capital) - $200,000 (materials) = $50,000 accounting profit.