$\"\"$

\

The diameter of the circular end of the tank is $\"\"$ .

\

The cylindrical tank has horizontal axis.

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The gasoline weighs $\"\"$ .

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The cylindrical tank is half filled.

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Consider the depth of the tank is $\"\"$ .

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The standard form of circle equation is $\"\"$ .

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Consider the center of the circular end of the tank is at origin.

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Substitute $\"\"$ and $\"\"$ .

\

$\"\"$

\

$\"\"$

\

$\"\"$

\

$\"\"$

\

$\"\"$ .

\

The horizontal length of the tank is $\"\"$ .

\

Therefore, $\"\"$ .

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The $\"\"$ ranges from $\"\"$ to $\"\"$ .

\

$\"\"$

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The fluid force is $\"\"$ .

\

Substitute $\"\"$ , $\"\"$ and $\"\"$ .

\

$\"\"$

\

$\"\"$

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Power rule of integration: $\"\"$ .

\

$\"\"$

\

$\"\"$

\

$\"\"$

\

$\"\"$

\

$\"\"$

\

$\"\"$

\

$\"\"$

\

$\"\"$

\

$\"\"$

\

Fluid force on a circular end of the tank is $\"\"$ .

\

$\"\"$

\

Fluid force on a circular end of the tank is $\"\"$ .