Using the phase diagram below $($figure $2)$ for the aluminium$-$magnesium oxide system, determine

i$.$ the phases present and

ii$.$ the composition $(wt\%Mg)$ of each phase and

iii. the amount of each phase for:

iv$.$ Draw what this $2$ components material could look like under the microscope.

a$.$ an aluminium$-$magnesium $(5wt\%A{l}_2{O}_3)$ alloy at $2000C.$

b$.$ an aluminium$-$magnesium $(20wt\%A{l}_2{O}_3)$ alloy at $2400C.$c$.$ an aluminium$-$magnesium $(93$ wt $\%A{l}_2{O}_3)$ alloy at $1600C$

Figure $2$: Aluminium$-$magnesium Oxide phase diagram