Final answer:
Economic concepts of supply and demand explain the situations of shortage and surplus. At $20, it's unable to definitively answer without additional information as it relates to the specific units of shortage or surplus in the options provided. Option D.
Step-by-step explanation:
To answer your question regarding the effect of a $2opt0 price, we need to understand the basic principles of supply and demand in economics. In Economics, a shortage or surplus occurs when the price of a good is either below or above the equilibrium price.
If at $20, there is a shortage, it means that the quantity demanded at that price surpasses the quantity supplied. In terms of options A and B, it's indeterminable because the quantity of the shortage is not given.
Conversely, a surplus occurs when the quantity supplied is greater than the quantity demanded. So In the cases C and D at $20, where there is either no surplus or a surplus of 8 units, it would mean that either the market is in equilibrium (Option C) or that the quantity supplied is exceeding the quantity demanded by 8 units (Option D).
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