explain please

Figure 12.23: xy diagram for ethanol(1)/ethyl acetate(2) and for chloroform(1)/tetrahydrofuran(2), both at a constant pressure of 1 bar. Note that the curves are intentionally unlabeled, but they can be identified based on information presented in Figs. 12.19 through 12.22 . 12.30. What is the composition of the liquid phase in equilibrium with a vapor-phase ethanol(1)/ethyl acetate(2) mixture of the following compositions at P=1 bar? (a) y1=0.1 (b) y1=0.2 (c) y1=0.3 (d) y1=0.45 (e) y1=0.6 (f) y1=0.8 (g) y1=0.9