Given data:
The total numbers of people are n=30.
(a)
The expression for the number of ways to select president, vice-president, secretary, treasurer, and historian is,
[tex]\begin{gathered} x=^{30}P_5 \\ =\frac{30!}{(30-5)!} \\ =\frac{30!}{25!} \\ =17,100,720 \end{gathered}[/tex]Thus, there are 17,100,720 ways to select president, vice-president, secretary, treasurer, and historian.