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recycle - v. to make something new from something that has been used before
dilemma - n. a situation in which one has to make a difficult choice
greenhouse gas emission - phrase, the release of gas that contributes to the warming of the earth's atmosphere by absorbing infrared radiation
carbon footprint - n. is the total amount of greenhouse gas emissions produced directly and in directly
smelt - v. to melt rock that contains metal in order to get the metal out
convenience - n. a quality or situation that makes something easy
biodegradable - adj. capable of being slowly destroyed and broken into very small parts by natural process
