The second dose of the COVID-19 vaccine is more likely to produce side effects than the first. The time between receiving the shot and the onset of side effects is called the lag time. Suppose according to one study, the lag times (among the subjects that reported side effects from a second dose of the vaccine) were normally distributed with a mean of 15 hours, with a standard deviation of 2 hours. Use the empirical rule to answer the following.

(a)
What is the probability that a person selected at random from among those that experienced side effects from their second dose of the vaccine had a lag time of less than 13 hours?

(b)
What is the probability that a person selected at random from among those that experienced side effects from their second dose of the vaccine had a lag time between 15 and 19 hours?