Question

Let us perform an activity based on Fermat's principle to understand refraction of light.
Fermat's principle
The path taken by a light ray between two given points is the path
that can be travelled in the least time.
ACTIVITY
1. Take a shallow (less Deep) opaque trough.
2. Put a coin in the trough.
3. Stand in a way that you can see the coin as shown in figure (a)
Figure (a)
Figure ibi​

Answer 1

Answer:

sorry I didn't understand