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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.

Which is an accurate description of the physical characteristics of poland? its fertile soil is found only along riverbanks, and its mountainous region in the northwest has few mineral resources. it is mostly flat with fertile soil except in the east and northeast, and the mountainous region in the south has large deposits of coal and copper. it is covered with thick forests, and it has large reserves of coal, petroleum, and natural gas. its landscape is dominated by plateaus, mountains, and high ridges, and it has large deposits of sulfur and copper in the northeast.

The next best alternative given up when making a choice is called the a. opportunity cost b. comparative advantage c. primary objective d. negative consequence select the best answer from the choices provided. a b c d