Answer
See explanation.
Work Step by Step
Apply Snell’s law at the 2 boundaries.
The angles are measured from the normal to the interface.
a. First, to the refraction from material X into the water.
$$n_a sin\theta_a= n_b sin\theta_b$$
$$n_X sin 25^{\circ}= 1.333 sin48^{\circ}$$
$$n_X=2.34$$
b. Finally, to the refraction from water into air.
$$n_a sin\theta_a= n_b sin\theta_b$$
$$1.333 sin 48^{\circ}= 1.000 sin\theta_{air}$$
$$\theta_{air}=82^{\circ}$$
