We don't have the item you were given so can't give an answer.
a
Many figures. For example, an ellipse.
yes
A circle and square.
There are infinitely many such. A valentine heart would be one well-known. example.
a
Then the figure has line symmetry.
Many figures. For example, an ellipse.
It depends on the irregular figure. A rectangle, for example, has two.
When you rotate it around a point found in the middle of the figure 180 degrees. For example, H does have rotational symmetry however, E doesn't
Shapes do not always have lines of symmetry. For example, if you have an irregular shape, it will not have a line of symmetry. I am quite certain though that all geometric shapes have a line of symmetry.
A figure has rotational symmetry if you can turn it about a figure.
A hexagon, for example, has six lines of symmetry. Three of them go to opposite vertices, and three go to opposite sides.
yes
square
The letters S and N have point symmetry but not line symmetry.
A parallelogram does not have a line of symmetry.