Writeacher, I urgently need your help to check a few things.

1) Which of them is the girl to whom you are enganged?
2) Paris, which I visited las year, is one of the most romantic cities I've been to/to which I've been/where I've been/where I've stayed/which I've been to/in which I was.
(I need to know the ones which are incorrect):
3) Is that the CD in which you are interested?
4) We've just received the computer, which/that/no pronoun we ordered last week (according to the rule the relative pronoun object can be omitted because the relative clause is defining).
5) On the challenge I'll take with me a backpack with food and drinks for two days, extra clothes and a compass.
6) I've got a rucksack on my shoulders.
I'm carrying a rucksack on my shoulders.
I'm wearing my hair tied at the back in a bun.
7) In my rucksack I've packed food for two days, a water bottle (?) and extra clothes.
8) What would you pack in your rucksack if you had to compete in the ten tors challenge?
9) I've got a rucksack in which I put (have put) everything I need for/on the challenge.

1. engaged

2. last year ... (all variations are correct, but I'd stick with the 1st and 3rd ones)

3. OK

4. Yes, and if you omit the relative pronoun, then you also delete the comma.

5. commas needed - do you see where?

6. All OK

7. commas needed...

8. Should "ten tors" have capital T's?

9. OK - all variations are fine.