I was wondering if anyone had specifics on clothing etiquette for Ethiopia. I am a teenage girl and there has been sparse information for my age group.

Specific questions:
1- Is it polite or just weird (as a tourist) to cover your head in a church?
2- How long should girls' pants or skirts be?
3- Is there any type of shoe that is unacceptable or impractical? (Obviously not high heels or anything, but...)
4- Must I have my shoulders covered or anything like that?

Thank you very much! :)