Assess speed (4)
I believe the answer is:
rate
I believe this is a double definition.
'assess' is the first definition.
(I know that rate is a type of assess)
'speed' is the second definition.
(the speed at which something happens)
(Other definitions for rate that I've seen before include "Price - class - speed" , "Judge" , "Tariff" , "See 11" , "Assess; speed" .)