Have you ever looked up the density of a substance ? You ought to try it. Go ahead. Pick a substance, then go online or open up an actual book and find its density. You will never see any particular volume mentioned along with the density . . . because it doesn't matter. The whole idea of density is that it describes the substance, no matter how much or how little you have of it. The density of a tiny drop of water under a microscope is the same as the density of a supertanker-ful of water.
Answer:
mgh= 10 x 8 x 10
= 800
but you can try 10 x 8 x 4^-1 x 10
The potentially harmful effects of mining can be reduced by A. Flushing mines with water.