Where are the questions so i can answer them?
There are several types of microscopes: compound microscopes 0 the most commonly used microscope, uses light illumination and the image that is seen is two dimensional, stereoscope- uses light illumination and the image that appears is 3 dimensional, confocal microscope - uses laser light ,scanning electron microscope - uses electron illumination.
Answer:
pfu/ml
Explanation:
Given -
Bacteriophage dilution
ml
Volume of bacteria and plate with top agar
ml
Number of plaques
pfu
Dilution (d) 
Final concentration of phage stock is equal to

Where pfu is the count of plaques
d is the dilution and v is the volume
Substituting the given values, we get -
pfu/ml