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(a) Fluid pressure:

Pressure is defined as the force per unit area over the surface of a body.

The pressure on an object at depth $\"\"$ in a liquid is $\"\"$ , where $\"\"$ is the weight density of the liquid per unit of volume.

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(b)

The force $\"\"$ exerted by a fluid of constant weight-density $\"\"$ (per unit of volume) against a submerged vertical plane region from $\"\"$ to $\"\"$ is

$\"\"$

$\"\"$ , where $\"\"$ is the depth of the fluid at $\"\"$ and $\"\"$ is the horizontal length of region at $\"\"$ .

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(a) The pressure on an object at depth $\"\"$ in a liquid is $\"\"$ .

(b) $\"\"$ .