The concept required to solve this problem is hydrostatic pressure. From the theory and assuming that the density of water on that planet is equal to that of the earth
we can mathematically define the pressure as

Where,
= Density
h = Height
g = Gravitational acceleration
Rearranging the equation based on gravity

The mathematical problem gives us values such as:



Replacing we have,


Therefore the gravitational acceleration on the planet's surface is
