Answer
At an angle of incidence of $~~49.0^{\circ}~~$ the reflected light will be completely polarized.
Work Step by Step
We can use Equation (33-49) to find the Brewster angle $\theta_B$ at the interface between water $n_1$ and glass $n_2$:
$\theta_B = tan^{-1}~\frac{n_2}{n_1}$
$\theta_B = tan^{-1}~\frac{1.53}{1.33}$
$\theta_B = 49.0^{\circ}$
At an angle of incidence of $~~49.0^{\circ}~~$ the reflected light will be completely polarized.
