Final answer:
After a 180-degree counter clockwise rotation using point k as the center of rotation, lines a and b swap positions.
Step-by-step explanation:
When you rotate lines a and b counter clockwise 180 degrees using point k as the center of rotation, you will notice that the lines have essentially flipped positions. Line a will now occupy the position previously held by line b, and line b will occupy the position previously held by line a.
For example, if line a was originally horizontal and line b was originally vertical, after the 180-degree rotation, line a will be vertical and line b will be horizontal.
This is because a 180-degree rotation causes the lines to rotate halfway around the center of rotation, resulting in their positions being swapped.