The UV rays cause sun spots due to reaction from the radiation.
The property of all ionic compounds that makes chalk particularly useful for writing on a chalkboard is : Hardness and Brittleness
Those properties make chalk leaves residues on the board every time friction happen between the chalk and the board
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A example of a nerve cell is a nerve cell
Answer:
<u><em>Current and WIND</em></u><u> cause water motion.
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