Situation: I am writing on the whiteboard farther from the cabinet while having the radiator in my six o'clock direction.
Alternative situations: Presenting my project in a meeting, I am writing a formula on a whiteboard, while someone on the chair behind me is asking a question. All the people at the table behind me are listening. I am in front of the classroom writing instructions on the whiteboard and my students are on computers behind me taking notes.
Question: What is behind me that is large in size?