spheres

Surface area of Spheres
Finding the surface area of a sphere
In lesson 10.7 a circle was described as a locus of points in a plane that are a given distance from a point. A sphere is the locus of points space that are a given distance from a point.
Finding the surface area of a sphere
A diameter is a chord that contains the center. As with all circles the terms radius and diameter also represent distances and the diameter is twice the radius
Theorem 12.11: Surface Area of s sphere
The surface area of a sphere with readius r is S=4πr2