Present perfect questions

  1. Where have you been?
  2. What have you been doing?
  3. Why have you come to this class?
  4. When have I got to arrive?
  5. Where have they been on holiday?
  6. Why haven’t you tidied up?
    Are all these present perfect questions correct?

They are though they may not always be the best tense to choose, especially number 4.