It has four because you only count the ones on the base man :P
How Many Edges And Vertices Has A Square Based Pyramid?
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5 faces and 4 edges and 5 vertices
10 and 9 I think
8 Edges and 5 vertices
It would have eight edges and one vertex. Four edges on the base and four rising edges coming to meet at one Vertex.
5 faces
8 edges
4 vertices
8 edges
4 vertices