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exposure – n. coming in contact with something
app – n. a mobile phone program that performs a special function
isolate – v. to separate from other people or things
frustrate – v. make someone feel annoyed or less confident
positive – adj. in a medical test, positive means the person being tested has a disease or condition
location – n. a place or position
notify – v. to tell someone officially about something
regional – adj. relating to or coming from a particular area
