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drone – n. an unmanned aircraft or ship guided by remote control or onboard computers
guarantee – v. to promise a result; to promise that
something will happen
radiation – n. waves of energy from something that produces
heat or light; energy from a nuclear substance, which can be dangerous
sensor – n. a device that detects or senses heat, light, sound, motion, etc., and then reacts to it in a particular way
stability – n. the quality or state of something that is not easily changed or likely to change
