$\"\"$

Initial volume of the gas is $\"\"$ cubic feet.

A pressure of gas is $\"\"$ pound per square foot.

Pressure $\"\"$ .

$\"\"$

The volume expands to $\"\"$ cubic feet due to pressure.

Work done by the gas as the volume of the gas expands from $\"\"$ to $\"\"$ is $\"\"$ .

Substitute $\"\"$ , $\"\"$ and $\"\"$ in the formula.

$\"\"$

$\"\"$ foot-pounds.

Work done by the gas is $\"\"$ foot-pounds.

$\"\"$

Work done by the gas is $\"\"$ foot-pounds.