Determine the depth at which the hydrostatic pressure of the water in the sea is 421kPa.

The hydrostatic pressure of sea water can be represented by the formula:

Р = ρ * g * h, where Р is the given hydrostatic pressure (Р = 421 kPa = 421 * 10 ^ 3 Pa), ρ is the density of seawater (by condition we take ρ = 1030 kg / m3), g is the acceleration of gravity (by condition we take g = 10 N / kg = 10 m / s2), h is the required depth.

h = P / (ρ * g).

Let’s perform the calculation:

h = 421 * 10 ^ 3 / (1030 * 10) = 40.87 m.

Answer: The seawater pressure will be 421 kPa at a depth of 40.87 m.