the temperature in five cities were 3f, -5 F, 7 F, -9 F, and -13 F. what was the mean temperature of five cities​

Monitors manufactured by tsi electronics have life spans that have a normal distribution with a standard deviation of 1800 hours and a mean life span of 20,000 hours. if a monitor is selected at random, find the probability that the life span of the monitor will be more than 17,659 hours. round your answer to four decimal places.