Answer:
1.153
Step-by-step explanation:
Refractive index of glass with respect to alccohol
=

=

Refractive index of glass with respective respect to alcohol
=

Critical angle C is angle made in denser medium by ray of light with the vertical on the surface. In this case it is 44 degree.
So ,
=

x = 1.66 \times \sin44
= 1.66 x 0.694
=1.153