Here is the 8.4 exercise:

Here is the 8.5 exercise:

Here is the 8.6 exercise:

Overall, these were great exercises for continuing our practice with lists. The one that stumped us the most was Exercise 4. We had gotten it right but were unsure why. After talking through the code though, we were better able to analyze what the issue was and why what we had come up with was correct. The other exercises were fairly straightforward, and we were able to work through them with little difficulty.