(4) Mindy and Peter are among the 6 candidates for a job. The order in which the candidates are interviewed is randomly decided. (a) Explain or show why there are exactly four possibilities for Mindy's and Peter's positions in the ordering if exactly 3 candidates are interviewed between them. (b) Find the probability that exactly 3 candidates are interviewed between them. (c) Find the probability that exactly 1 candidate is interviewed between them