All my work is shown in the image.
Answer:
There are 650 cannonballs
Step-by-step explanation:
If you look closely in the picture, you can see that:
- 1st row has 1 ball
- 2nd row has 4 balls
- 3rd row has 9 balls
- 4th row has 16 balls
etc. etc.
We can see that the number of balls is the square of the row number. There are a total of 12 rows. So, rest of the rows has:
- 5th row has 25 balls
- 6th row has 36 balls
- 7th row has 49 balls
- 8th row has 64 balls
- 9th row has 81 balls
- 10th row has 100 balls
- 11th row has 121 balls
- 12th row has 144 balls
If we add up all those, we get total number of balls:

There are 650 cannonballs
Sphere
The radius of the sphere is the only unknown variable need to find the volume of a sphere.
Step-by-step explanation:
Sphere is a geometrical three dimensional round figure with every point on its surface equidistant from its center. It is a three dimensional representation of a circle. A line which connects from the center to the surface is called radius of the sphere.The diameter of the sphere is the longest straight line which passes through the center of the sphere.
The volume of sphere is given by:
Volume of sphere(V) = 
where V is the volume of the sphere
r is the radius of the sphere
= 3.14
Hence the only unknown variable to find the volume of a sphere is the radius.