Area Country Subdivision
Area is the quantity that expresses the extent of a two-dimensional figure or shape, or planar lamina, in a plane.
The simplest area for a figure is the rectangle (length x width)
A = lw (rectangle)
A = s2 (square)
A = 1/2 X b X h (triangle)
A = πr2 (circle)
A = 4πr2 (sphere)
Archimedes showed that the surface area of a sphere is exactly four times the area of a flat disk of the same radius, and the volume enclosed by the sphere is exactly 2/3 of the volume of a cylinder of the same height and radius.
See also …
en.wikipedia.org/wiki/Area
