In this task, find the most appropriate number to replace the blank (indicated with _ ) and express it in words.
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Question: Walruses walk with _ flippers over ice and snow.

Answer: four


Question: Metals often crystallize in a _ dimensional version of the hexagonal closest packed structure.

Answer: three


Question: Scarcity occurs when, at a _ price, quantity demanded is greater than quantity supplied.

Answer:
zero