Answer
a). (3) less than the angle of incidence.
b). $35.17^{\circ}$
Work Step by Step
a). As light travels into a denser medium, the light ray bends towards the normal. So (3) is the answer.
b). By Snell's law :-
$n_{1}sin\theta_{i}=n_{2}sin\theta_{r}$
Now, $n_{1}=1$, for air
$n_{2}=1.33$, for water
and $\theta_{i}=50^{\circ}$
Thus, $\theta_{r}=sin^{-1}(\frac{1\times sin50^{\circ}}{1.33})=35.17^{\circ}$
