TASK DEFINITION: Given scientific fact as input, generate the question from this fact such that it can be answered from the input.
PROBLEM: Diffusion is the term for the movement of molecules from an area of high concentration to an area of low concentration.

SOLUTION: What is the term for the movement of molecules from an area of high concentration to an area of low concentration?

PROBLEM: Incubation is when birds keep their eggs warm while the embryos inside develop.

SOLUTION: What is it called when birds keep their eggs warm while the embryos inside develop?

PROBLEM: Natural resource type of resource is limited in supply and cannot be replaced except over millions of years.

SOLUTION:
What type of resource is limited in supply and cannot be replaced except over millions of years?