In the submenu. And it's useful not to wrestle with the unregistered filetypes or just RMB on some .exe to be able to unpack it.

I've used 7zip for a decade and just a couple months ago I discovered in addition to everything I knew about already it also offers it also has a SHA-256 checksum tool in it's context menu! It is legitimately one of the most useful utilities on my system.

You can choose what shows up in that context menu or choose to show nothing at all, you can also choose to have it cascade (which I believe is the default).

Arguably very useful options. For instance, try using 7zip to extract an .exe installer sometime -- right click on it and extract it into its own dir and see what is in it.