A train is traveling at a constant speed and has traveled 67.5 miles in the last 12 hours. Which equation shows the proportional relationship between the distance, d, and the time, t,
that the train has traveled?

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.