In accounting, the cost incurred in past or historical financial statements is classified as the actual cost, which is the cost that has been incurred and is already recorded in the financial statements. This differs from budgeted or standard costs, which are estimates of future expenditures.

The selling price variance measures the impact of price fluctuations on revenue. It is calculated as (Actual Price - Budgeted Price) multiplied by Actual Quantity Sold. This metric is crucial for sales managers to understand whether revenue deviations are due to changes in market pricing strategies or changes in the volume of goods sold during the period.

A favorable variance occurs when actual results are better than the budgeted expectations. In the context of operating income, earning more than the amount originally planned is considered a positive outcome for the business. This indicates that the company either generated higher revenues or managed its costs more effectively than anticipated during the budgeting process.

Step cost functions are considered nonlinear because they remain constant over a specific range of activity and then 'step up' to a higher level once that range is exceeded. Unlike variable costs that change proportionally with activity, step costs exhibit a discontinuous pattern, making them a classic example of nonlinear cost behavior in managerial accounting.

Capital budgeting is the strategic process used by businesses to evaluate potential major projects or investments. It involves analyzing long-term capital expenditures, such as purchasing new machinery, constructing new facilities, or developing new products, to determine which investments will provide the highest return and align with the company's long-term financial objectives and growth strategy.

Net initial investment refers to the total cash outlay required to initiate a project. It typically includes the purchase price of assets, installation costs, and any necessary increases in net working capital. While the prompt mentions cash inflows, the term 'net initial investment' is standard for describing the total capital commitment at the start of an investment project's lifecycle.

In cost accounting, a spending variance measures the difference between actual costs incurred and the budgeted costs for a specific activity. When actual costs for items like plant leasing, administrative overhead, or equipment depreciation are higher than the budgeted amounts, the variance is classified as unfavorable. This indicates that the organization spent more than planned, necessitating an investigation into the causes of the cost overrun.

A cost center is a department or function within an organization where the manager is responsible for controlling costs but is not responsible for generating revenue or making investment decisions. Examples include maintenance departments, human resources, or accounting departments, where the primary objective is to provide services efficiently while staying within a predetermined budget.

The price variance represents the difference between the actual price paid and the standard or budgeted price. Mathematically, Price Variance = Actual Price - Budgeted Price. Given a variance of $20 and a budgeted price of $70, the actual price is $70 + $20 = $90. This indicates the actual cost was higher than the budgeted amount.

The adjusted allocation rate approach restates all overhead entries in the general ledger by replacing the budgeted allocation rates with the actual cost rates calculated at the end of the period. This ensures that the ledger accounts reflect the actual costs incurred rather than estimates.