To develop this problem we will apply the concepts related to the apparent depth.
The apparent depth is a relationship between the measured distance and the refractive coefficient of the medium in which the measurement is made.
Theoretically, this coefficient for water is n = 1.33 and the formula can mathematically be described as
[tex]d_{app} = \frac{d}{n_w}[/tex]
Now what you need to find is the real distance, rearranging the equation
[tex]d = d_{app}n_{w}[/tex]
Replacing,
[tex]d = 1*1.33[/tex]
[tex]d = 1.33 m[/tex]
Therefore the actual distance from the fish to the surface is 1.33m
