In a spectrometer experiment a student measures a glass prism with an angle of 45.0°…

Step 1. The angles. $i = \dfrac{45.0^\circ + 25.0^\circ}{2} = 35.0^\circ$ and $r = \dfrac{45.0^\circ}{2} = 22.5^\circ$.

Step 2. The glass. $n = \dfrac{\sin 35.0^\circ}{\sin 22.5^\circ} = \dfrac{0.5736}{0.3827} = 1.50$.

Step 3. The liquid. $i = \dfrac{60.0^\circ + 46.3^\circ}{2} = 53.15^\circ$ and $r = 30.0^\circ$. So $n = \dfrac{\sin 53.15^\circ}{\sin 30.0^\circ} = \dfrac{0.8002}{0.5000} = 1.60$.