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

Example Input: If an air mass forms over an ocean it is called a maritime air mass.
Example Output: If an air mass forms over an ocean it is called what type of air mass?

Example Input: Stringed instruments can help show the relationship between tension and frequencies in strings.
Example Output: Stringed instruments can help show the relationship between tension and what in strings?

Example Input: Warm water from the equator mixes with cold water from the poles.
Example Output:
Warm water from the equator mixes with cold water from where?