Differentiate fixed costs and variable costs. 1  Total cost is the sum of fixed and variable costs.  Variable costs change according to the quantity of a good or service being produced. The amount of materials and labor that is needed for to make a good increases in direct proportion to the number of goods produced.
Southern Copper Corporation is an American-based copper producer with major operations in Mexico and Peru. Grupo Mexico currently owns 75.1% of the company, which produced 487 thousand metric tons of copper in 2010. Major assets include the Cuajone and Toquepala mines in Peru and the Cananea mine in Mexico.
Reynolds Metals Company is the worldâs third largest aluminum and packaging company. As a fully integrated manufactuer, distributor, and marketer of primary and value-added fabricated aluminum products, the company operates 100 manufacturing facilities in 24 nations.