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A certain virus infects five in every 400 people. A test used to detect the virus in a person is positive 85% of the time when the person has the virus and 8% of the time when the person does not have the virus. Let A be the event "the person is infected" and B be the event "the person tests positive."

a.Using Bayes' Theorem, when a person tests positive, determine the probability that the person is infected

b.Using Bayes' Theorem, when a person tests negative, determine the probability that a person is not infected