I remember this from art ... Mono-chromatic we only used one color to create different shades so the answer is one
So you can "read in between the lines" so to say, Teachers want you to re-read what you have read to develop a deeper understanding.
This lines could be seen as examples of sensory imaginary. More precisely it is connected to smell because of the potato and sight because of how this person is found "sitting, surrounded.." it might be said that the combination of these two images could give the reader a vision of what the writer is trying to convey.
Context, please? I would then be able to help you out.