Anyone able to help with this?

[tex]W = 23.7°[/tex]
Step-by-step explanation:
The formula given is the statement of Snell's law of refraction. We are given the following:
[tex]I_a = 1.0003[/tex]
[tex]I_w = 1.3[/tex]
[tex]A = 31.5°[/tex]
So we need to find the angle of refraction W. Starting with Snell's law,
[tex]\dfrac{I_w}{I_a} = \dfrac{\sin A}{\sin W} \Rightarrow \sin W = \left(\dfrac{I_a}{I_w}\right)\sin A[/tex]
Plugging in the given values, we get
[tex]\sin W = \left(\dfrac{1.0003}{1.3}\right)\sin{31.5°} = 0.402[/tex]
Solving for the angle W, we then get
[tex]W = \sin^{-1}(0.402) = 23.7°[/tex]