Answer:
Prokaryotic Cells are cells that lack Cell Nucleus so the answer is bacteria
This is easily explained saying that the frictional force between the books and the paper isn't big enough to produce a displacement in the books. The displacement in the books doesn't happen because the frictional force between the books and the surface they are standing on is bigger than the paper's one.
Noble gasses ( insert gases)
It must be a virtual image, because this is the only kind of image it can produce.
