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

Example Input: Pangaea began breaking apart 250 million years ago.
Example Output: How many millions of years ago did pangaea begin breaking apart?

Example Input: Collision theory states that chemical reactions occur when atoms, ions, or molecules collide.
Example Output: What states that chemical reactions occur when atoms, ions, or molecules collide?

Example Input: Pyramid ecosystem is used to show energy flow through the trophic levels.
Example Output:
What is used to show energy flow through the trophic levels?