перевод текста Costs should include opportunity costs of all recourses used in production. Opportunity cost of a commodity is the amount an input can obtain in its best alternative use (best use elsewhere). In particular, costs include the owner’s time and effort in running a business. Costs also include the opportunity cost of the financial capital of the financial capital used in the firm. Aiming to get higher profits, firm obtain each output level as cheaply as possible. Firms choose the optimal output level to receive the highest profits. This decision can be described in terms of marginal cost and marginal revenue. Marginal cost is the increase in total cost when one additional unit of output is produced. Marginal revenue is the corresponding change in total revenue from selling one more unit of