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false alarm –n. a warning of danger that does not exist
app –n. (application) a computer program designed to do a specific task or set of tasks
alert –n. something like a message or loud sound that tells people of danger
shift –n. a planned or scheduled period of time that someone works
automated –adj. done automatically by a machine or system, not done by a person
siren –n. device that make loud sounds that are meant to warn people of danger
