Derek designed an experiment to demonstrate interactions between earth systems. he cleared a patch of land in his backyard and poured a glass of water from a height of 12 inches above the ground. a depression was formed on the land at the spot where the water hit the ground. what does derek's experiment best demonstrate?

Derek's experiment best demonstrates the effects of gravity, that force made the water go down and  hit the ground, the effect of that was a depression.

The definition of Hydrosphere is all the water of earth surface, so the water represents Hydrosphere.

The definition of Geosphere is the surface of Earth, when the water fell down and touched the ground it caused an interaction between Hydrosphere and Geosphere.

if they have a finite resultant

r = ρ x length / area  

ρ = r x area / length  

ρ is in ohm-meters  

in basic units, it is m³kg/s³a²  

i think this is it.