Event module questions

Hey! 

I have a couple of questions regarding the event module.

My situation is that I have 1 event with 5 sessions.

1. I have included when building the event that i wanted reminder emails 7 dags before the day of the event. Will that reminder email be included in every session?

2. If I want to change a date for a session, how can I do that? I only see the dates for the sessions as read only fields. 

3. When doing my registration form, how do I manage that a contact can register themselves to more then one session?

I have two more question about forms that i need to know regarding the event:

4. In form builder, where is the duplicate check? it is the email only? or is it every filed i match to a CRM filed? 

5. If i want to see the answers from a form in different ways (adding filters and forms groups) what is best practice? For example, I want to see how many answered yes to a specific question.