Question

If a tank has water to the depth of 10m, calculate the pressure exerted by it

Answer 1

Need to know size of tank. 10m^3 exerts less pressure than 100m^3.

Answer 2

Here is a calculator tool. For water the pressure is approximately 1 atm for every 10 m depth
http://www.calctool.org/CALC/other/games/depth_press

Answer 3

If you want absolute pressure, add one atm for the pressure of air on the surface, thus about 2 atm

Answer 4

If you use Dr. Bob's calculator, it adds that one atm at the surface for you
p = Patm + rho g h