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: The values of strangeness assigned to various particles are based on decay systematics.

Answer: The values of strangeness assigned to various particles are based on what?


Question: The cell starting meiosis is called a primary oocyte.

Answer: The cell starting meiosis is called a what?


Question: Momentum is directly related to both mass and velocity.

Answer:
Momentum is directly related to both mass and?