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

[EX Q]: Compression zones is the opposite of rarefaction zones, where air molecules in waves are loosely packed.
[EX A]: What is the opposite of rarefaction zones, where air molecules in waves are loosely packed?

[EX Q]: The water in some springs are hot because they're heated by hot magma.
[EX A]: The water in some springs are hot because they're heated by what?

[EX Q]: Earth is the only planet in the solar system that has water, which is essential for human life, present in all three of its states.
[EX A]:
Earth is the only planet in the solar system that has what element, which is essential for human life, present in all three of its states?