Answer:
Part 1)
------>

Part 2)
------>

Part 3)
------>

Part 4)
------>

Explanation:
we know that
The largest cross sectional area of that sphere is equal to the area of a circle with the same radius of the sphere
Part 1) we have

The area of the circle is equal to

so

Solve for r


Find the volume of the sphere
The volume of the sphere is

For

substitute


Part 2) we have

The area of the circle is equal to

so

Solve for r


Find the volume of the sphere
The volume of the sphere is

For

substitute


Part 3) we have

The area of the circle is equal to

so

Solve for r


Find the volume of the sphere
The volume of the sphere is

For

substitute


Part 4) we have

The area of the circle is equal to

so

Solve for r


Find the volume of the sphere
The volume of the sphere is

For

substitute

