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Math problem (geometry) in junior one.
1。 The difference between a cylinder and a prism is that the bottom of the cylinder is round and the cross section is round. The prism has a polygonal bottom and a polygonal cross section. An edge is a quadrilateral and a parallel edge. If the bottom is polygonal, it is called a few prisms, if the bottom is triangular, it is called a triangular prism, and if it is quadrilateral, it is called a quadrilateral (that is, a cuboid). Wood is a common cylinder, and prisms and cuboids are common prisms.

* * * Similarity: Three-dimensional space has height. Similarity between cylinder and prism;

They are all cylinders, and the volume can be calculated by the general formula of cylinder volume: volume = bottom area × height.

2。 The difference between a cone and a pyramid is that one face of the pyramid is a polygon and the other faces are triangles with a common vertex. The cone is surrounded by a circular bottom and a fan-shaped side.

If a cone (pyramid or cone) has a base area of S and a height of H, its volume is V-cone = 1/3Sh.

If the radius of the cone bottom is r and the height is h, then its volume is: V cone = 1/3π r2h.

Similarities: they are all cones, and the bottom surface corresponds to a vertex.