The order of rotational symmetry of a circle is

The least angle of rotation of a regular pentagon is

The order of rotational symmetry of regular octagon is

Which squares should be shaded to make the given figure symmetric?

Which of the following does not have a line of symmetry?

What is the least number of squares that must be added so that the line $\mathrm{AB}$ becomes a line of symmetry?

What is the least number of squares that must be added so that the line  becomes a line of symmetry?

What is the least number of squares that must be added so that the line $\mathrm{AB}$ becomes a line of symmetry?