Answer:
The correct options are;
1) The shape maps unto itself after a rotation of 270 degrees
2) The smallest angle of rotational symmetry is 90 degrees
3) The shape maps unto itself after a rotation of 180 degrees
Step-by-step explanation:
We note that the shape of a cross which consists of two equal members (segments) bisecting each other at right angles such that when a member is placed vertically upright, the other member will be horizontal, therefore we have;
After rotation by 90 degrees, the vertical member will become horizontal and vice versa
After rotation by 180 degrees, the vertical member will become horizontal and vice versa again
Similarly, after rotation by 270 degrees, the once vertical member will become horizontal and the horizontal member will become vertical
