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

[EX Q]: A electron microscope is used to see extremely small objects.
[EX A]: What type of microscope is used to see extremely small objects?

[EX Q]: The name for a matter that has a fixed volume and a fixed shape is solid.
[EX A]: What is the name for a matter that has a fixed volume and a fixed shape?

[EX Q]: The values of strangeness assigned to various particles are based on decay systematics.
[EX A]:
The values of strangeness assigned to various particles are based on what?