GENERAL KNOWLEDGE

Detailed explanation-1: -Proportional costs are those costs that are directly pro-portional to the volume of production. The cost function of proportional costs is given by a line which goes through the origin.

Detailed explanation-2: -Variable costs change in proportion to the quantity of output. As production quantity increases, the cost increases; as production quantity decreases, so do the costs. Most accounting textbooks depict variable costs as varying directly with volume.

Detailed explanation-3: -Detailed Solution. Marginal cost is directly proportional to its Variable costs. Marginal cost is the increase in the total cost when one more product is produced.

Detailed explanation-4: -Answer and Explanation: A cost that changes in proportion to changes in volume of activity is called c) a variable cost. Variable costs are those tied directly to production and rise and fall depending on what work a business does.