Given scientific fact as input, generate the question from this fact such that it can be answered from the input.

Q: Some meteorites are made of iron and nickel and are thought to be very similar to the core of the earth.

A: Some meteorites are made of iron and nickel and are thought to be very similar to what part of the earth?
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Q: 40 m/s north of the following represents the velocity of a moving object.

A: Which of the following represents the velocity of a moving object?
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Q: Although it is not vital to humans, calcitonin is important for calcium homeostasis in adults of some species in vertebrates group characterized by backbones.

A:
Although it is not vital to humans, calcitonin is important for calcium homeostasis in adults of some species in what group characterized by backbones?
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