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: Wilting occurs when water lost by transpiration is not replaced by absorbtion from room.

Answer: What occurs when water lost by transpiration is not replaced by absorbtion from room?


Question: Socket secures teeth in the mouth.

Answer: What secures teeth in the mouth?


Question: The concentration of the hydrogen ion in a solution can be calculated when the ph is known.

Answer:
The concentration of the hydrogen ion in a solution can be calculated when what is known?