19!, ie factorial 19 which is 19 x 18 x 17 x 16 etc down to 4 x 3 x 2 x 1.
This is a BIG number: 121,645,100,408,832,000
8! = 40320 ways.
4
24
One... numbers
you can arrange 8 pictures 28 different ways
24 ways
you can arrange three beads 9 different ways.
120 ways
7!=5040
8
Only One
There are six, but it is traditional to list them least to greatest,