Answer:
When the object has not moved/changed shape
There is two answers to that because there are two different forms of cells that being animal and plant cells. The cell is surrounded by a cell or plasma membrane. Unlike the animal cell the plant cell also has a cell wall surrounding it. This is made of cellulose and is very rigid.
A)
size = (number of minor spaces x 10μm) / number of ocular spaces
= (2 x 10) / 1
= 20μm
b)Since the RBC has a size of 8μm and the bacterium 20μm, the bacteria is bigger. The Bacterium is bigger than the RBC by 20μm / 8μm
Hence the bacterium is 2.5 times bigger than the RBC.