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

[EX Q]: Natural resource type of resource is limited in supply and cannot be replaced except over millions of years.
[EX A]: What type of resource is limited in supply and cannot be replaced except over millions of years?

[EX Q]: Multiple genes mutations is usually necessary to develop cancer.
[EX A]: What is usually necessary to develop cancer?

[EX Q]: In the case of a light bulb, electricity is converted to light and thermal energy.
[EX A]:
In the case of a light bulb, electricity is converted to light and what kind of energy?