I came across this question
```
A lightsource of diameter 10cm is placed 2m underneath the surface of a pool, a person 
5m away from the edge of the pool saw a circle of light emitting from the lamp. 
Calculate the maximum diameter of the circle of light seen by the person. 
(Use refractive index = 1.33)
```

I figured this would be something similar to that of Snell's Law and drew the diagram below:
[![enter image description here][1]][1]


  [1]: https://i.sstatic.net/PEgXg.png

The answer is indeed about 4.66m, however I am quite puzzled as to how the person could see the entire circular shape of light, given that some rays are travelling away from the person?