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sticking point – n. something that people disagree about and keeps them from making progress in discussions
drought – n. a time with very little rain
global – adj. involving the whole world.
sanitation - n. promotion of hygiene and preventing disease by removing sewage and trash
aviation –n. the business or practice of flying airplanes and helicopters
carbon off-sets – n. a credit that an organization can buy to negate a carbon footprint
battery – n. a device placed inside a machine to supply it with electricity
turbine – n. an engine that has a part with blades that spin by pressure from air
frequency – n. the number of times that something, like a sound wave, is repeated in a period of time
