Stella posted a new weekly challenge:

Obviously, the numbers under the ball are the key.

After looking at them hard, you will notice that the length of the line is double the length of the week's challenge answers.

Teacher tells us to "reflect on what we know", so we can maybe use the mirrored version and the original version.

Another observation is that the numbers 1 - 15 seem to be present, so we'll probably have to assign the letters from the answers to the solution.

Solved: