$\"\"$

The volume of the spherical balloon with radius $\"\"$ is $\"\"$ .

Find the function that the amount of air to inflate the balloon from a radius $\"\"$ inches to a radius $\"\"$ inches.

Then the resultant function is subtract $\"\"$ .

$\"\"$

$\"\"$ ( Formula : $\"\"$ )

$\"\"$

Take out $\"\"$ as a common factor.

$\"\"$

The resultant function is $\"\"$ .