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If you are looking at a dodecahedron, Which of these can be created by a planar cross section?
MORE THAN ONE ANSWER MAY BE CORRECT!
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To answer this question, you FIRST must know what a dodecahedron is.
To see the figure, look in this Wikipedia article
https://en.wikipedia.org/wiki/Dodecahedron
Next you need make an effort and turn on your imagination.
It does not require a transcendent thinkig, but some minimal effort from your side.
Below I put my answers to the list. Where it is appropriate, I put some short explanations.
Options:
Isosceles triangle - Yes, it is possible. Take a plane section near any vertex. The further explanation is not needed.
Scalene triangle - Yes, it is possible. Take a plane section near any vertex. The further explanation is not needed.
Rectangle - Yes, it is possible. Take a plane section near and parallel any edge. Then adjust it appropriately.
trapezoid - Yes, it is possible. Take a plane section near and parallel any edge. Then adjust it appropriately.
Dodecagon - I don't know.
Equilateral triangle - Yes, it is possible. Take a plane section near any vertex. Adjust it appropriately.
Pentagon - Yes, it is possible. Take a plane section near and parallel to any face. The further explanation is not needed.
Concave polygon - No. You always will have a convex polygon in any plane section (if your original dodecahedron was convex).
When you will evaluate my answers, keep in mind that this test is for you - not for me.
And remember, that I just helped you as much as I could . . .
