The answer is artificial reef. Its a man made underwater structure typically built to promote marine life areas with a generally features bottom to control erosion, block ship passage or improve surfing. Artificial reef improve marine life in a certain area and deprive a new location for fishermen to fish and which works to ease the pressure on natural reefs.
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Answer:
About 3000 years, which is a very long time
Explanation:
Most of the money in Afghanistan is not suprisingly used to purchase weapons, amoury and military confinements. This obviously doesn't come cheap. So in thought that war would get them rich, making civilians happier with life in Afghan, everything went wrong and they had a downfall. There is not a single battle going on meaning weapons cannot be used. Meaning it was a waste of money. They then sold few amounts of guns, armoury and soldiers to the U.S and got not much money. This is why they are what they are today.
Its d four because it make sense