Situation: I am sitting on a chair facing the table with no other chairs in the same row on my right and the window is in front of me.
Alternative situations: Having written the agenda on a whiteboard behind me, I am leaning over the chair and check the plan of presentation on a monitor in my eleven o'clock direction. My seat is located directly behind the radiator but across the table so I am warm all day long but not too hot.
Question: Which object behind me needs a marker to write on?