i$-$Butanol forms a minimum$-$boiling$-$point azeotrope. The t$-$x diagram for this system is shown in figure.

The i$-$Butanol concentration $($wt$\%)$ of the azeotrope is:

s$-$ ur $y-$mun nactuon, vater

Select one

a$.61\mathrm{.}7$

b$.66\mathrm{.}04$

c$.69\mathrm{.}1$

d$.56\mathrm{.}3$