The name for such a hole is "caldera" which is a word of Spanish origin meaning "a pot" or a "cooking pot" (thing of cauldron!) - and this word is used because it resembles the shape of this hole.
Often the Calderas are filled with water forming lakes and often there is an island in the middle of the water.
Answer:
In its most general sense, the term "world" refers to the totality of entities, to the whole of reality or to everything that is. The nature of the world has been conceptualized differently in different fields. Some conceptions see the world as unique while others talk of a "plurality of worlds".
Answer:
"The tilt of the Earth's spin axis with respect to the plane of its orbit about the sun (the ecliptic plane) is important for a habitable Earth. The Earth's spin axis is tilted 23.5° with respect to the ecliptic, giving moderate seasons and preventing temperature extremes anywhere on the planet"
Explanation:
No barriers to trade from nation to nation