When economists refer to "demand," they are speaking of:a) how much everyone wants of all products bought and sold in the nation. a schedule of amounts of a product that buyers would purchase at alternative prices in a given time period. b) a single price and quantity combination. c) a "desire" for a product rather than a "need" for the product regardless of the price. d) all of the above.

d) all of the above.

Explanation:

All of the above statement correspond to different definitions of demand that economists use on a daily base.

Statement A) refers to aggregate demand, which is roughly equivalent to GDP.

Statement A.2) refers to demand schedule, which is also simply referred to as demand in the press, or in informal contexts.

Statement B) refers to an equilibrium quantity demanded, which occurs when supply and demand meet under an equilibrium price.

Statement C) refers to quantity demanded because it is not always relevant, when talking about demand, whether the good demanded is a necessity or a luxury.

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