Answer:
1320 sets
Step-by-step explanation:
 This problem brothers on selection without repetition, so we will be using permutation to solve this problem.
Given
n= 12 ,which is  the number we are choosing from
r= 3, which is the number of committee(president, vice-president, and​ secretary-treasurer.)
[tex]= \frac{n!}{(n-r)!}[/tex]
Substituting we have
[tex]= \frac{12!}{(12-3)!}\\\\ = \frac{12!}{(9)!}\\\\= \frac{12*11*10*9!}{9!}[/tex]
[tex]= 12*11*10= 1320[/tex]
