Question

which two are characteristics of mixtures? each part keeps its properties. a mixture has at least four compounds. you cannot separate the parts after they are combined. you usually can easily separate the parts after they are combined.

Explanation:

In a mixture, the components retain their individual properties. Also, mixtures can usually be separated by physical means easily. A mixture can have any number of components (not necessarily at least four), and the parts can be separated after combination.

Answer:

Each part keeps its properties.
You usually can easily separate the parts after they are combined.