The question asks you to prove A v C
This is what I have. Everything is correct until the last question, #11
1. A V C
2. ~BvC
3.(new subproof) B
4. (new subproof ~B
5. contradiction contradiction intro 4,3
(end subproof from 4-5)
6. ~BvC V Intro 2
(end subproof from 3-6)
7...