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

[Q]: Simple kind of diffusion do small hydrophobic molecules squeeze through lipid molecules.
[A]: What kind of diffusion do small hydrophobic molecules squeeze through lipid molecules?


[Q]: Bones are made up of different types of tissue.
[A]: Bones are made up of different types of what?


[Q]: Snow and hail are two types of frozen percipitation.
[A]:
What are two types of frozen percipitation?