A regular pentagon has five axes of symmetry.
0 if it is irregular, 8 if it is regular. Probably some numbers in between are possible, too.
3
Octagon
i think 5
In a regual shape the number of axes of symmetry is equal to number of sides.
A polygon need not have any axes of symmetry. It can have at most n axes where n is the number of sides that the polygon has.
it's a hexagon
It has 5 axes of symmetry
An irregular hexagon has no axes of symmetry. A regular hexagon, on the other hand, has 6 axes of symmetry: three lines joining the midpoints of opposite sides, and three lines joining opposite vertices.
Not sure about a duodecagon, but a regular dodecagon has 12 axes of symmetry.
A regular pentagon has five axes of symmetry.
The square.
cube
0 if it is irregular, 8 if it is regular. Probably some numbers in between are possible, too.
3
12