At shallow depth, h, the pressure in the ocean is simply given by P=P0+ρgh, in which ρ is the density of water and P0 is the air pressure. As we go deeper, the high pressure causes the water to compress and become denser. Which of the following sketches illustrates the correct dependence of the pressure on the depth h?
a) [Graph a: Linear relationship starting at P₀]
b) [Graph b: Curved relationship starting at P₀]
c) [Graph c: Different curved relationship starting at P₀]
d) [Graph d: Another curved relationship starting at P₀]