Case #1: The number of possible assignments is 1. Case #2: The number of possible assignments is 2. Case #3: The number of possible assignments is 6. Case #4: The number of possible assignments is 24. Case #5: The number of possible assignments is 120. Case #6: The number of possible assignments is 720. Case #7: The number of possible assignments is 5040. Case #8: The number of possible assignments is 40320. Case #9: The number of possible assignments is 362880. Case #10: The number of possible assignments is 3628800. Case #11: The number of possible assignments is 39916800. Case #12: The number of possible assignments is 479001600.