Delete Cognite data questions

Hi,
I have some questions on Cognite. Would you please help?
1. Files
1.1 To delete Cognite files, after deleting the files do we need to delete the documents also? 
1.2 After we create the files, the documents are created by Cognite automatically, but it seems there are some random delay to create the document, why?
1.3 what is the concept of document in Cognite? Why is it created? Any documents on that?
2. sequences
2.1 To delete Cognite sequences, after deleting the sequences do we need to delete the datapoints also? 
3. timeseries
3.1 To delete Cognite timeseries, after deleting the timeseries do we need to delete the datapoints also?
4. delete order for containers, views 
4.1 to delete all FDM data in a space, the order of deletion should be edges, nodes, containers, view versions, data models, space. And the containers should be deleted first then delete the view versions, right?

Thank you!

Alice