9. For the two figures below, the Gibbs free energy (g) is plotted versus the mole

fraction of a in a binary system of solids a and b. Three distinct solid phases can

form (a, ß, y). Each figure is at constant pressure and temperature but the

pressure and temperature are not the same for the two figures. Describe the

phases present at each composition for the two systems and list their

compositions for the entire range of mole fraction of a.