Organizers, Chairs and Discussants

How shall we indicate that there are two of us organizing the panel?

I am organizing a panel and was wondering if the chair has to be one of the paper presenters of the panel or can he/she just perform as chair.

Both of our co-chairs will present papers, but they will not necessarily be the first two papers on the panel. How should we indicate this?

Can I organize and chair two different sessions? One is a panel and the other one is a workshop or a roundtable.

Can a panel organizer be included as chair and/or paper presenter in the same panel she/he organizes?

Can a person organize two panels, even if they are presenting a paper in only one of them?

Is it mandatory to include a chair and an organizer in each session?

Is it mandatory to include a discussant in each session?