Answer:
Caverns are created when moving groundwater mechanically weathers sediment and transports it elsewhere, leaving behind large empty spaces.
Explanation:
The movement of groundwater causes erosion that is responsible for the formation of caves. These caves are formed due to mechanical weathering of rocks. Mechanical weathering plays an major role in creating caverns by dissolving of limestone rock due to acidic water that reacts with limestone and removes it with the passage of time that forms caves. The normal pH water can't perform this job due to no reaction occurs with limestone.
A river's width and depth increases as more water is added from tributaries.
Answer: The Earth is a closed system for matter
That is a list of all basic elemental materials on our planet. Because of gravity, matter (comprising all solids, liquids and gases) does not leave the system.
In other words: they sailed from Hennø in Norway, heading due west towards Greenland, between Shetland and the Faroes and south of Iceland