<P> A production--possibility frontier (PPF) or production possibility curve (PPC) is a curve which shows various combinations of set of two goods which can be produced with the given resources and technology where the given resources are fully and efficiently utilised per unit time...One good can only be produced by diverting resources from other goods, and so by producing less of them . This tradeoff is usually considered for an economy, but also applies to each individual, household, and economic organization . </P> <P> Graphically bounding the production set for fixed input quantities, the PPF curve shows the maximum possible production level of one commodity for any given production level of the other, given the existing state of technology . By doing so, it defines productive efficiency in the context of that production set: a point on the frontier indicates efficient use of the available inputs (such as points B, D and C in the graph), a point beneath the curve (such as A) indicates inefficiency, and a point beyond the curve (such as X) indicates impossibility . </P> <P> PPFs are normally drawn as bulging upwards or outwards from the origin ("concave" when viewed from the origin), but they can be represented as bulging downward (inwards) or linear (straight), depending on a number of assumptions . A PPF illustrates several economic concepts, such as scarcity of resources (the fundamental economic problem that all societies face), opportunity cost (or marginal rate of transformation), productive efficiency, allocative efficiency, and economies of scale . </P>

What does a point inside the curve on a ppf represent
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