Answer:
A downhill
Explanation:
A runoff happens when water drags sediment from a rock over a sloping terrain. Thus, water drags the eroded fragments of a rock in favor of gravity, pushing these fragments downwards. This is very common in mountainous and steep regions, without vegetation cover, where erosion caused by runoff is very high.
Hi there,
Speed of sound in water is approximately 1500 meters per second (the exact speed depends on the depth of water and its density) and the speed of sound in air is approximately 340 meters per second. So sound is almost 4.4 times faster in water than in air. I hope this helped :)