Answer: Its not rare and this isn't a question so stop deleting my answer.
Answer: b. square root of 27 cm
Explanation:
i got it right on the quiz
The Gobi Desert spans across Mongolia and China. It specifically runs across northwestern and northern China and Southern Mongolia. The Gobi is a large desert region in Asia and is a rain shadow desert formed by the Himalaya range blocking rain-carrying clouds from the Indian Ocean from reaching the Gobi territory. The Gobi is most notable for it being the location for several important cities in the Silk Road and as part of the Great Mongol Empire.
They are called fringing reefs. They grow directly from shore and form borders along the shoreline.
When a fringing reef continues to grow upward from a volcanic island that has sunk entirely below the sea level, an atoll is formed. Atolls are usually circular or oval in shape, with an open lagoon in the center.
The fringing reef is the most common type of coral reef. They however tend to be very sensitive to human induced pollution in the water and are easily destroyed by such.