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A square port hole is submerged in seawater with an area of $\"\"$ .

Assume the center of the square is 15 feet below the surface.

Therefore, $\"\"$ .

The fluid force is $\"\"$ .

The fluid pressure is $\"\"$ .

The weight density of sea-water is $\"\"$ .

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Substitute corresponding values in the formula.

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Fluid force on a square plate is $\"\"$ pounds.

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Fluid force on a square plate is $\"\"$ pounds.