No, it is not possible.
yes
Assuming that the question refers to a regular octagon (not a regualr otagon), the answer is no.
Not a regular one.
No it can't
Strictly speaking, no, because a semi-regular tessellation must be based on regular polygons and rhombi are not regular polygons. However, octagons and rhombi can be used to make a non-regular tessellation.
yes
Yes, they will.
An octagon can be used to create a tessellation, but an octagon cannot tessellate on its own.
false, there would be gaps.
No Internat angle of a regular octagon is 135°. No multiple of 135° will make 360°. Thus at any point there can be at most two octagons and a 90° gap. Ratty
You cannot use a regular octagon on it's own to make a tiling pattern without any gaps. However a regular Octagon and a square can be used together to make a tessellation. Many people think that regular octagons tesselate on their own because they do not appreciate the need for no gaps.
Assuming that the question refers to a regular octagon (not a regualr otagon), the answer is no.
The only shapes which will make a regular tessellation are:an equilateral trianglea squarea regular hexagon.
Not a regular one.
A regular tessellation or semi-regular tessellation or none.
No it can't
Strictly speaking, no, because a semi-regular tessellation must be based on regular polygons and rhombi are not regular polygons. However, octagons and rhombi can be used to make a non-regular tessellation.