The two substances are rock (molten and solid) and metal (solid + liquid).
Layers of the earth from the outside in:
1. crust. hard rock/dirt/ground. Shell
2. mantle. melted rock and stuff. Egg white
3. core. Outer core - liquid. Inner core- solid. Nickle and iron. Yolk
<span>Altostratus Clouds, they are thin enough to see through :)</span>
I think the answer is Traction
Lymphocytes is the answer.
the answer to ur question is eggs bc eggs come from an animal