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

Q: Constant random motion trait of particles causes even cold objects to have some thermal energy.

A: Which trait of particles causes even cold objects to have some thermal energy?
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Q: There are three quarks in each proton and neutron.

A: How many quarks are in each proton and neutron?
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Q: Tiltmeters are used to measure the angle of the slope of a volcano.

A:
Which instruments are used to measure the angle of the slope of a volcano?
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