C. Coral Reefs, The Great Barrier Reef actually.
The North Sea has very important natural resources such as oil and natural gas. Oil is a mixture of organic compounds, mainly hydrocarbons insoluble in water, it is also known as crude oil or simply crude and gas natural which is an important source of fossil energy released by its combustion.
Answer/Explanation:
Photosynthesis is important for all living organisms because it provides the oxygen needed by most living creatures for survival on the planet.
Answer: D. It can melt to a depth of a few meters in summer, then refreeze in winter.
Explanation:
Permafrost is ground which remains frozen for two or more years. Permafrost consists of soil, rock and sand fused together by ice. Mostly found in areas in high altitude, the Arctic, Antarctica, it is common in periglacial environments where temperatures are below freezing
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The topmost layer of permafrost can melt in summer and refreeze in winter. This thawing and refreezing produces a ground pattern called columnar joints similar to the one formed when molten lava cools.