Chromium$-$Nickel $(Cr-Ni)$ phase diagram is given below in molar and phase In the diagram, it is seen that $1$CrNi$2$ compound is formed.

a$)$ Overwrite the phase regions that are not defined in the phase diagram.

b$)$ Element ratios, phase ratios and the resulting phases of the phases formed at the point indicated with $"a".$

Calculate the grain types ratios.

c$)$ Element ratios, phase ratios and the resulting phases of the phases formed at the point indicated with $"b".$

Calculate the grain types ratios. Please show in the diagram.