Consider a $Pb-45\%-Sn$ alloy. Determine

$($a$)$ if the alloy is hypoeutectic or hypereutectic:

$($b$)$ the composition of the first solid to form during solidification;

$($c$)$ the amounts and compositions of each phase at $184C$;

$($d$)$ the amounts and compositions of each phase at $182C$;

$($c$)$ the amounts and compositions of each microconstituent at $182C$; and

$($f$)$ the amounts and compositions of each phase at $25C.$