Turn the given fact into a question by a simple rearrangement of words. This typically involves replacing some part of the given fact with a WH word. For example, replacing the subject of the provided fact with the word "what" can form a valid question. Don't be creative! You just need to rearrange the words to turn the fact into a question - easy! Don't just randomly remove a word from the given fact to form a question. Remember that your question must evaluate scientific understanding. Pick a word or a phrase in the given fact to be the correct answer, then make the rest of the question. You can also form a question without any WH words. For example, "A radio converts electricity into?"

[EX Q]: Fact: Slowing the growth of bacteria keeps food fresh.
[EX A]: What does slowing the growth of bacteria do for a food?

[EX Q]: Fact: Vertebrates have a complete digestive system and a closed circulatory system.
[EX A]: What do all vertebrates have?

[EX Q]: Fact: melting is when something part of a colloidal system is heated above its melting point.
[EX A]:
Melting is when something that is part of what is heated above its melting point?