Given scientific fact as input, generate the question from this fact such that it can be answered from the input.
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Question: An acorn growing into an adult tree will take the longest time to observe.

Answer: Which of these will take the LONGEST time to observe?


Question: When the phosphorus element - whose name means "light bringing" - was first isolated, scientists noted that it glowed in the dark and burned when exposed to air

Answer: When what element - whose name means "light bringing" - was first isolated, scientists noted that it glowed in the dark and burned when exposed to air?


Question: Distance is the term for the length of the route between two points.

Answer:
What is the term for the length of the route between two points?