So the question is asking for time.
Time= distance / speed
120/30
4
Therefore answer is d
A heat pump that uses work to move heat
I think the correct answer is D: Potential Energy.
C. is the answer to this question
Darcy's law is a phenomenologically derived constitutive equation that describes the flow of a fluid through something that is porous. Henry Darcy, who came up with this law, based the experiments of doing this through sand.