### Description

The surface area of a geometric shape can be calculated from key measurements. This can be used to determine the surface area of cells, organs or lesions.

 Shape Formula for Total Surface Variables cube 6 * a^2 a = length of side box 2 * ((a * b) + (b * c) + (c * a)) a, b, c = lengths of sides cylinder 2π * R * (R + h) R = radius of base h = height cone π * R * (R + SQRT((R^2) + (h^2))) R = radius of base h = height sphere 4 * π * (R^2) R = radius torus (π^2) * a * b a = radius from center of inner space to innermost edge; b = radius from center of inner space to outermost edge

where:

• Cylinders and cones also have a "lateral surface" which is total surface without the circular end(s)..

 Shape Formula for Lateral Surface Variables zone and segment of sphere with 1 base 2 * π * R * h r = radius of the sphere h = distance to top zone and segment of sphere with 2 bases 2 * π * R * h R = radius of the sphere h = distance between planes lune (surface segment on sphere) 2 * R * (angle in radians) R = radius of sphere; angle = angle subtended perpendicular to the central axis

where:

• The equation for the zone and segment of sphere with 2 bases looks a little funny to me. This would mean that the surface area for a zone near the equator would be the same for a zone of the same height near the pole.