Using one integrated accounting system creates a single source of truth for all financial data, which boosts the credibility of financial reports. When data are entered, stored, and processed in one place, the figures come from the same underlying records, reducing inconsistencies and errors that can erode trust. The integrated system also provides a complete, easily traceable audit trail and supports standardized policies and procedures, making it easier for external users—such as investors, lenders, and regulators—to rely on the statements. The idea that external audits could be eliminated isn’t correct, since independent verification remains important. The belief that internal controls would be reduced isn’t accurate either; a single system typically strengthens controls through consistent access restrictions, approval workflows, and uniform processes. And the notion that complexity increases with a single system is opposite to reality, as it tends to simplify data handling and reconciliation rather than add layers of complication.

Product-level cost data in internal reports is valuable because managers need granular cost information to make informed decisions and to evaluate how each product performs. This level of detail supports planning and control actions such as pricing decisions, product mix adjustments, and resource allocation, as well as evaluating profitability and holding managers accountable for the costs under their control. External tax reporting and external disclosures don’t rely on this level of product-by-product detail for decision making; they focus on broader financial results and compliance rather than the ongoing internal assessment of individual product lines.

Opportunity cost in capacity decisions is the value of the best alternative use of the scarce capacity you forego by producing more of one product. Here, moving from 80% to 90% capacity changes output from 192 units (0.8 × 240) to 216 units (0.9 × 240). That means full capacity is 240 units, and the increase uses 24 additional units of capacity. The per‑unit opportunity cost is the value of one extra unit of capacity in its next best use. That value is given as 5.78 (in the relevant currency) per unit. Therefore, the opportunity cost per additional unit is 5.78, and for the 24 extra units the total would be 24 × 5.78 if you need the aggregate value.

Internal accounting systems are built to help managers plan, control, and evaluate performance by providing timely cost information. They track inputs, processes, and outputs, then compare actual results to standards or budgets. This variance analysis highlights where production is not meeting targets, pointing to inefficiencies such as waste, bottlenecks, or idle capacity. With that information, management can investigate root causes and take corrective actions to improve efficiency and reduce costs. While data from internal systems can inform external financial reporting, their primary purpose is internal decision making and control. The idea that it costs more than it contributes isn’t consistent with how these systems are intended to add value through better resource use and performance monitoring.

Economic profit reflects not only explicit costs but also the value of resources foregone in the next-best use. Accounting profit is revenue minus explicit costs. Economic profit goes further by subtracting implicit costs (the opportunity costs). So economic profit = revenue − explicit costs − implicit costs, which is the same as accounting profit minus opportunity costs. This makes the statement true regardless of the numbers: you can have positive or negative economic profit depending on whether revenue covers both explicit costs and the foregone alternatives. Taxes affect accounting profit, but the relation to opportunity costs remains the same.