What is the volume of an tetrahedron with edge length of 1?
Pick one: A) sqr(2)/12 = 0.11785113 B) sqr(2)/14=0.13571785 C) sqr(2)/12=0.15798562 D) sqr(2)/13=0.21254478 E) sqr(2)/12=0.12457896
The following can be derived using the Pythagorean theorem:   The height of a face is 3.5/2.   The area of any face is 3.5/4.   The distance from any corner to the center of a joining face is 1/3.5.   The height of the tetrahedron is (2/3).5   The area is 1/3*base*height =   (1/3) * 3.5/4 * (2/3).5 = 21/2/12.
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What is the volume of an tetrahedron with edge length of 1?