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Which of these is a drawback of using natural gas? a. it is fairly safe for use in homes.b. it burns more cleanly than crude oil products.c. scientists have developed new ways of extracting it.d. during its extraction, groundwater can be contaminated.

What is most often given a value of zero to describe an object’s position on a straight line? displacement reference point distance ending location

Deep-ocean and are created by convergent boundaries of an ocean and continental crust