Answer:
There are 0.1 mililiters in 5 milimeters saline.
Step-by-step explanation:
A 2 % suspension means that 2 % of the volume of a given substance per each 100 milimeters of saline. That is:


Where:
 - Suspension ratio, dimensionless.
 - Suspension ratio, dimensionless.
 - Saline volume, measured in milimeters.
 - Saline volume, measured in milimeters.
 - Substance volume, measured in milimeters.
 - Substance volume, measured in milimeters.
Given that  and
 and  , the volume of the substance is:
, the volume of the substance is:
 
 

There are 0.1 mililiters in 5 milimeters saline.