A Nb$-60wt\%W$ alloy is heated to $2800C.$ Determine $($a$)$ the composition of the solid and liquid phases in wt$\%$; $($b$)$ the amount of each phase in $wt\%$; and $($c$)$ assuming that the density of the solid is $16\mathrm{.}05\frac{g}{c}{m}^3$ and that of the liquid is $13\mathrm{.}91\frac{g}{c}{m}^3,$ determine the amount of each phase in vol$\%.$

Weight percent tungsten

$8$