Find the rate of change for the situation. you run 7 miles in one hour and 21 miles in three hours. 7 miles per hour 3 hours 7 miles 3 miles per hour

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.