It effects the environment because it can cause unstability in the food web and biotic and abiotic factors
The sentence that is true is A galaxies are holder together by gravity it is not D because galaxies are real its not C because they are not being pulled apart and its not B because galaxies are held together.
During Physical Change there would be a re-arrangements of atoms or molecules, changes of the arrangement may be change in the distance between atoms or molecules, change in the crystal form.
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