<PRE><B>Question 1077036</B>
9 unique letters to chose from...

9 choices for first letter * 8 choices for 2nd letter = 72

72*10 = {{{highlight(720)}}}

This assumes:
1. MY and YM (for example) are distinct.
2. In forming a word, the first letter chosen is not available as a choice for the 2nd letter (no replacement).

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Another tutor said 9C2.  If assumption #1 is valid, 9C2 is incorrect.  If assumption #1 is invalid, 9C2 is correct.    
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