Identify the vertex or the ! ! a. (-4,0)b. (-3, 1)c. (1,-3)d. (-1,-3)

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.