Question

chalk is made of trillions of microscope skeleton fossil of plankton​

Answer 1

Chalk is composed of planktonic skeletons and is therefore made of micro-fossils. In fact, the coccolithophores that comprise chalk are small even by planktonic standards and are therefore termed nanno-fossils.

Answer 2

Answer:

England's White Cliffs of Dover, one natural example of this phenomenon, were formed nearly 100 million years ago. The skeletons sank to the ocean bed, and the cliffs rose from the ocean due to a shift in the Earth's crust, Gizmodo explains.

Of course, some of the most beautiful things in life have an unsavory scientific explanation. Take for instance the sand that makes up Hawaii's beaches—it comes from parrotfish poop. According to the National Oceanic and Atmospheric Administration (NOAA), "The fish bite and scrape algae off of rocks and dead corals with their parrot-like beaks, grind up the inedible calcium-carbonate reef material (made mostly of coral skeletons) in their guts, and then excrete it as sand."

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