Waves depends on density and elasticity of the medium
I don't know what your answers were but the more "stuff" there is the more energy it takes to freeze or boil it. Hope this could help
Both of them are a hope this helps
Answer: When a substance is pure, it is composed of one type of molecule. For example, table salt is only composed of (more or less) salt molecules, while seawater has water and salt molecules. A more complicated example of a non - pure substance is soil. It has many different types of nutrients and compounds.
C. pain reliever
ex. tylenol, aleve, etc.
