 
<translate> Mene ne tambaya don wannan ma'anar ma'ana, da kuma amsar da ta dace? Wannan shi ne bayanin da ya dace: Ruwa yana motsa ruwa ta hanyar nauyi kawai, tare da ɗan ƙaramin gangare na ƙasa a cikin bututun dutse, tubali, ko kankare; gwargwadon gangaren, saurin gudana.  Amsar ita ce: nauyi <eng> What was the question for this implicit rationale, and corresponding answer?
This is the relevant information: Aqueducts moved water through gravity alone, along a slight overall downward gradient within conduits of stone, brick, or concrete; the steeper the gradient, the faster the flow.
 The answer: gravity 