Which statement can be made about both waves? They will speed up. They will increase the density of their medium. They will slow down. They will decrease the density of their medium.

The teacher is mostly talking about the distillation of a mixture

It is a mixture. simply put, a compound must be pure, that is, of only one chemical structure and composition. a mixture is made of different chemical substances (i.e. elements, molecules, compounds) that are not chemically bonded to each other, but instead physically grouped together, as in the case of gasoline (a homogeneous solution).

Pretty sure it's d. heterogeneous is separated by physical properties.