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Page: 3220 Tuesday, March 31, 2015 
The Diameter of a circle or sphere is equal to 2 times the Radius:
Diameter = 2 * Radius
Figure #1., The Diameter of a circle

Figure 2., Diameter is 2 * Radius 
The Circumference of a circle or a sphere is equal to 6.2832 times the Radius.
Circumference = 6.2832 * R
The Radius of a circle or sphere is equal to the Diameter divided by 2.
R = D / 2
The Circumference of a circle or a sphere is equal to 3.1416 times the Diameter.
The Area of a circle is equal to the Radius of the circle multiplied by the Radius and then this number multiplied by 3.1416.
Area = R * R *
Area = R * R * 3.1416
This number will be in square inches or square millimeters, depending on the measurement system used.
The Area of a circle is equal to the Diameter of the circle multiplied by the Diameter and then this number multiplied by 3.1416 and then this total is divided by 4.
Area = D * D * 3.1416 / 4
Area = D * D * / 4
This number will be in square inches or square millimeters, depending on the measurement system used.
The Area of a Cylinder is equal to 6.2832 ( 2 * ) times the radius of the Cylinder, times the sum of the Radius plus the Height.
Area = 2 * 3.1416 * R * ( R + H )
Area = 2 * * R * ( R + H )
This number will be in square inches or square millimeters, depending on the measurement system used.
The Volume of Cylinder is equal to the radius of the Cylinder, multiplied by the Radius, and this number multiplied by by 3.1416, then this number is multiplied by the length of the Cylinder.
Volume = 3.1416 * R * R * H
Volume = * R *R * H
This number will be in cubic inches or cubic millimeters, depending on the measurement system used.
The Area of a Sphere is equal to the Square of the Radius of the sphere multiplied by 12.566 ( 4 * ) or Pi times the Diameter squared ( * D * D ).
Area = 12.566 * R * R
Area = 4 * * R * R
Area = * D^2
This number will be in square inches or square millimeters, depending on the measurement system used.
The Volume of a Sphere is equal to the Radius of the Sphere, multiplied by the Radius again. Then this number is multiplied by the radius again. Then this number is multiplied by 12.566. and the result is divided by 3.
Volume = 12.566 * R * R * R / 3
Volume = 4 * * R * R * R / 3
This number will be in cubic inches or cubic
millimeters, depending on the measurement system used.