Given a fact, create a question that can be answered using the fact. Construct the question such that it is unambiguous, has a unique answer and the answer can be given using the fact.

Q: Fact: a complete electrical circuit is a source of electrical energy

A: Which is a complete circuit?
****
Q: Fact: bad weather decreases visibility while driving

A: Driving during a snow storm or strong thunderstorm is a bad idea because bad weather makes it?
****
Q: Fact: the mantle is a layer of the Earth

A:
The mantle is?
****