Answer: option c. the mixing of solute and solvent molecules
Explanation:
I would say C. Permable
Google def.(of a material or membrane) allowing liquids or gases to pass through it.
"a frog's skin is permeable to water
Porous- (of a rock or other material) having minute spaces or holes through which liquid or air may pass
It is B: Fixed volume, takes the shape of the container
By adding together the number of protons and neutrons and multiplying by 1 amu, you can calculate the mass of the atom.
I would pick the first option in the third option