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the cost of mining is extremely low compared to the money earned from mining, creating income to improve the environment.

not always but somethings can be reproduced in a laboratory.

the statements that apply here about binary star system are

"have stars that might appear to wobble"

"often have one star that is brighter than other"

a binary star is a star system consisting of two stars revolving around their common barycenter. systems of two or more stars are called multiple star systems.