Final answer:
A price ceiling below $25 per box is a binding price ceiling in this market.
Step-by-step explanation:
A price ceiling is a legal maximum price that can be charged for a good or service. It is binding if it is set below the equilibrium price in the market. In this case, if the price ceiling is set below $25 per box, it will be a binding price ceiling because it will prevent the market price from rising to the equilibrium level.
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