How many edges and faces of a cuboidal-shaped building can be seen, when it is observed from the middle of its roof? Also, draw the building as it appears from this position. Only show the visible edges.

How many vertices, edges and faces are visible and how many are hidden in the given figure, where dotted lines represent the hidden edges.

There are two rods $AB$ and $CD$ and a hollow cylinder represented in the figure. The dotted line shows the hidden portion. You have to tell how the two rods are arranged. Which one is passing from inside the cylinder?

Look at the figure at right and answer the following :

Name the edges which meet in the vertex $H$

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Look at the figure at right and answer the following:

Name the faces which meet in the edge $AB$.

Look at the figure at right and answer the following:

Name the faces which are adjacent to $BFGC$.