How does the ozone layer high in the atmosphere protect life on earth? answers?

Johnny rode his bike to a friend's house 4 blocks down the street in his neighborhood. he immediately rode back home once he realized his friend was not able to play. what was his displacement for the total bike ride? how did you determine this? what could we use as a reference point to determine he was in motion during his bike ride? why can you use it as a reference point

Which coal field location is related to coal fields in the eastern united states and supports the theory of continental drift? eastern india southern africa western australia northern south america

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