In the library

We have 8 different books in a library.
In how many ways can they be arranged?
In how many ways can they be arranged if 3 specific volumes must appear in a fixed given order?
In how many ways can they be arranged if three specific volumes must appear consecutively (in any order)?

Final Answer:

a =  40320
b =  120
c =  720

Step-by-step explanation:

$$\begin{gathered} n=8 \\ a=n!=8!=40320 \end{gathered}$$

$b=(n-3)!\cdot 1=(8-3)!\cdot 1=120$

$c=(n-3)!\cdot 3!=(8-3)!\cdot 3!=720$

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