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Sphere
A sphere has only 1 curved face. It has no edges and no vertices.

Nets

A net is a 2-diamensional figure that can be folded into a 3-dimensional object.

Net of a Cube

Take a cubical object and trace all its faces on a sheet of paper.
What is the shape of all the six faces?

They are all squares of the same size. Thus, we see that

a cube can be made from six squares joined together in a
particular manner.
We have many more nets (arrangements of these squares) that can be folded up to form a cube.

We can also form nets with 5 square faces. In this case it will be a box with no lid.

Exercise 10.4

1. Write the name, number of faces, edges and vertices for each of the following shapes.

(a) (i) Name: ______ (b) (i) Name: ______

(ii) Faces: _______ (ii) Faces: _______
(iii) Edges: ______ (iii) Edges: ______

(iv) Vertices: ____ (iv) Vertices: ____

(c) (i) Name: ______ (d) (i) Name: ______

(ii) Faces: _______ (ii) Faces: _______

(iii) Edges: ______ (iii) Edges: ______
(iv) Vertices: ____ (iv) Vertices: ____