----------  *AREAS*  ----------

    Areas of Geometric Figures

Square                side**2
Rectangle             length * width
Parallelogram         base * height
Triangle              base * height / 2
Regular n-polygon     (1/4) * n * side**2 * cot(pi/n)
Trapezoid             height * (base1 + base2) / 2

Circle                pi * radius**2
Ellipse               pi * radius1 * radius2

Sphere (surface)      4 * pi * radius**2
Cylinder (surface)    2 * pi * radius * height
Cone (surface)        pi * radius * side
Torus (surface)       pi**2 * (radius2**2 - radius1**2)

   Source--Spiegel, Murray R.  Mathematical Handbook of Formulas
           and Tables.  Schaum's Outline series in Mathematics.
           McGraw-Hill Book Co., 1968.