The big thought quiz

Hey I'm posting a quiz with 8 questions and I know all the answers... Here's the quiz

1. 53266x43976

2. 32246684-45337

3. 5854+32466-3244

4. 676554355665 divided by 55

5. 46425-425

6. 57435-4435+53

7. 53746-54545

8. 53639+363738