Situation: I am using the trash can and discarding paper towel I grabbed from the paper towel dispenser to my right.
Alternative situations: Standing over the trash bin opposite the mirror and the two sinks as I dry my hands with a paper towel. I am discarding used paper towel into trash can in front of me, one I got from the dispenser in front of me to my left side.
Question: How many sinks are there behind me?