A regular tetrahedron is a polyhedron with four faces, each of which is an equilateral triangle, as shown. A solid regular tetrahedron is cut into two pieces by a single plane cut.
Which of the following could not be the shape of the section formed by the cut?
Select one option, then click Submit.
a pentagon
a square
a rectangle that is not a square
a trapezium
a triangle that is not equilateral
Select an option, then submit.
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