This is a variable costs graph.

Variable costs: are those costs that vary depending on a company's production volume; they rise as production increases and fall as production decreases. Variable costs differ from fixed costs such as rent, advertising, insurance and office supplies, which tend to remain the same regardless of production output.   

Fixed Costs: In management accounting, fixed costs are defined as expenses that do not change as a function of the activity of a business, within the relevant period. For example, a retailer must pay rent and utility bills irrespective of sales.

Total Cost : The total cost is the amount of money spent by a firm on producing a given level of output. Total costs are made up of fixed costs (FC) and variable costs (VC).

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