Given:
The diameter of the ball is 2.5inches.
So the radius is

The height of the cylinder is,

Required:
To find the Volume of the empty space.
Step-by-step explanation:
Now the volume of the one ball is,

Now the volume of the three ball is,

The volume of the cylinder is,

The volume of the empty space is = volume of the cylinder - volume of the balls.

Final Answer:
Volume of the empty space is
