Given a scientific question, generate a correct answer to it.

Ex Input:
The law of conservation mass states that matter cannot be created or what?

Ex Output:
destroyed

Ex Input:
What is a hydrocarbon in which the carbon chain joins to itself in a ring?

Ex Output:
cyclic hydrocarbon

Ex Input:
What is the general name for a wave that travels along the surface of a medium?

Ex Output:
surface wave