Yes
Yes
Yes.
regular hexagon
No. Each interior angle of a regular pentagon is 108 degrees. In order for tessellation to be possible, the sum of the angles meeting at a point must be 360 degrees. That is to ensure that all the space around that point is covered. But 108 is not a factor of 360 so it is not possible.
You have to specifically give the problem with the dots, but it can form all equilateral triangles.. .. . .. . . .
Yes
Yes.
regular hexagon
A regular tessellation or semi-regular tessellation or none.
Place the dodecagons so that every third side of a dodecagon is adjacent to another. In the gaps that are formed insert four equilateral triangles so that these touch a pair of dodecagons. Finally, fill the gap between the triangles using a square.
No. Because tessellation is about using lost (infinitely many) copies of a polygon to cover a surface, One polygon does not comprise a tessellation.
No. Each interior angle of a regular pentagon is 108 degrees. In order for tessellation to be possible, the sum of the angles meeting at a point must be 360 degrees. That is to ensure that all the space around that point is covered. But 108 is not a factor of 360 so it is not possible.
You have to specifically give the problem with the dots, but it can form all equilateral triangles.. .. . .. . . .
Yes it can
There is no such thing as a seni-regular tessellation. A semi-regular tessllation is a tessellation using two regular polygons: for example, octagons and squares together.
No, not normally
yes