Cultural norms are usually written down and in accurate form true or false

That statement is false.
cultural norm usually passed from one generation to another without any form of writing.
For example, it is considered as a cultural norm in japan to bow down when you're introducing yourself to another people. But it's not written in any of Japanese legal regulations and people wouldn't be subjected to punishment if they don't do it.

Hope this will !

Ibelieve its c not quite sure.