I have nine books and have room to display only four of them at a time on my bookself. How many different ways could I do this?

So to do this on paper I’d usually write out four blanks. One to represent each spot on the shelf. Then think about how many options you have for the first spot, 9. Now that you’ve used one, you second spot can only have 8 options. Since we’ve used two the third spot only has 7 options now. Finally the fourth spot has only 6 options. To get the answer we not multiply these four numbers
9x8x7x6= 3,024

The domain is 100 becuase i said so ok. jk its 00 jk again its r jk again and again its 75jk im always kiffing okaydbdbekufir83gc84vrudnmm as 8ehehenenrn vr 0eh339520252026ee6ee8e9