A square pyramid will not have any curved faces.
None.
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There are no curved edges on a triangular pyramid.
There are none
none
There are no curved edges, but it does stack.
None. All faces on a pyramid are flat.
There are infinitely many possible answers. A square based pyramid is one.
None.
This is a popular topic, discussed in many places on the web. The attached link is one place that I like. If you want to look for others just google for surface area square pyramid.
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