If an object maps onto itself after being rotated 180 degrees or less about a line, it has

  rotational symmetry

Step-by-step explanation:

That's the definition of rotational symmetry: the object maps to itself after rotation of less than one full turn.

The number of different rotational angles at which the object maps to itself defines the order of the rotational symmetry.

rotational symmetry

Step-by-step explanation:

If an object maps onto itself after being rotated 180 degrees or less about a line, it has rotational symmetry.

answer: a) (0,0), (1,1), (2,8), and (3,27).

step-by-step explanation:

0^3=0

1^3=1

2^3=8

3^3=27

in effect, the exponential equation for this would me y=3^x. each x-coordinate cubed is giving the y coordinate, so a is your answer : )