Choose the correct answer: who, whom, which or whose

1. He bought all the tools who whom whose which are required to fix his old car.
2. This is the doctor who whom whose which helped Sara recover from her illness.
3. This is the girl who whom whose which he fell in love with in Madrid
4. She managed to pass the exam in spite of all the difficulties, who whom whose which didn't surprise people who knew her.
5. These are the kids who whom whose which parents were were arrested..
6. Give me the plate who whom whose which is on the table.
7. I don't know who whom whose which did it.
8. The criminals, two of who whom whose which managed to escape, broke into a bank downtown.
9. The police identified the murderer who whom whose which fingerprints were on the knife.
10. I know the candidate who whom whose which I am going to support in the next elections.