1-A lead (Pb)-tin (Sn) alloy of composition 30 wt% Sn is slowly heated from a temperature of 100C. (15 pts)

a- At what temperature does the first liquid phase form?

b- What is the composition of this liquid phase?

c- At what temperature does complete melting of the alloy occur?

d- What is the composition of the last solid remaining prior to complete melting?

e- At 200C, which phases are present and what are their weight fractions?