According to Snell's law,
[tex]n_1\sin \theta_1=n_2\sin \theta_2[/tex]The refrative index of water is 1.333 and the refractive index of air is 1.
Substitute the known values,
[tex]\begin{gathered} (1)\sin \theta_1=(1.333)\sin 43.5^{\circ} \\ \sin \theta_1=(1.333)(0.688) \\ \theta_1=\sin ^{-1}(0.917) \\ =66.5^{\circ} \end{gathered}[/tex]The angle above the horizontal is calculated as,
[tex]\begin{gathered} \theta_1=90^{\circ}-66.5^{\circ} \\ =23.5^{\circ} \end{gathered}[/tex]Thus, the actual elevation angle of Sun above the horizontal is 23.5 degree.
