We can see that points A, B, C and D are all still coplanar points. Point E is not coplanar with the original four points. But if I pick any group of three of the points, even a group containing point E, those three points will be coplanar. The reason is the statement given above - any three points in 3-dimensional space determine a plane.
Definition of solubility. 1  1 : the quality or state of being soluble. 2  2 : the amount of a substance that will dissolve in a given amount of another substance.
SOLUBILITY is understood as a maximum amount of solute that dissolves in a solvent at so called equilibrium. In chemistry an equilibrium is a state where reactants and products reach a balance-no more solute can be dissolved in the solvent in the set conditions (temperature, pressure).