there are 3 unknown substances a, b, and c that need to be classified as an element, mixture or compound.. substance a can be broken down by a physical change. substance b cannot be broken down by a chemical or physical

Answer 1

change. Substance c consists of two or more different elements chemically combined in a fixed ratio.

Based on the given descriptions, substance a is a mixture, substance b is an element, and substance c is a compound.