Cross sections - geometry help?

Question

abbles · Answer

The cross section of a square pyramid taken perpendicular to the base produces which 2-dimensional shape?

I think the answer is a triangle but I'm not sure.  Also, does it have to be a specific triangle?

miracrown · Answer

I think it depends on where is the cross section, if it passes the top point 
it will be a triangle. If it is somewhere else, it could be a triangle or a trapezoid. So yes yes, triangle is definitely one of the possibilities !

abbles · Answer

Okay, thank you!  Do you have time for one more question?

miracrown · Answer

It depends what the question is.

abbles · Answer

What is the diagonal cross section of a cylinder?

abbles · Answer

I thought the answer was an ellipse, but the choices are: sphere, rectangle, circle, great circle, or triangle.

miracrown · Answer

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its a sphere. 
 Only a vertical cross section could be a rectangle, cross section parallel to the base is a circle - so I would choose circle.