The number of ways that 4 books can be arranged on a shelf are= 24. That is option 2.
To calculate the number of ways 4 books can be arranged is the find the permutation.
That is ,
4! = 4×3×2×1
4! = 24
Therefore, the number of ways that 4 books can be arranged on a shelf are= 24
Learn more about permutation here:
https://brainly.com/question/1216161
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