How many 2 letter codes can be made using the letters A, B, C (no repetition)?, 3, 6, 2, 1, How many different 3 digit numbers can be formed from the digits 1, 2, and 3 (no repetition)?, 9, 7, 6, 5, A teacher chooses and arranges 2 helpers from 4 students. How many possible arrangements are there?, 12, 7, 8, 20.

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