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app – n. a program for a smartphone or other device that performs a special function
isolate – v. to separate from other people or things
trace – v. to find the origin of something
fellow – adj. used to describe people who share the same interests or situation
location – n. a place or position
transmission – n. the process of passing something from one person to another
positive – adj. in a medical test, positive means the person being tested has a disease or condition
