At the time of case, most software was available for purchase. Thus, price of encryption software is its one-time purchase cost, not an annual subscription fee.

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2. Some costs and some benefits are likely one-time and others recurring.
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4. Revenue is another term for sales. It is gross inflow in to a company; it is 'top line' in income statements and is often called "Sales." To calculate income or profit, companies then subtract a number of costs. These costs include actual cost of product (referred to as Cost of Goods Sold), salaries, rent, utilities, interest, taxes, and other items. The 'bottom line' (income or profit) is usually expressed as a percentage of sales and is often called "margin".
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