The Jackson Engineering Company has a training program designed to upgrade the supervisory skills of production-line supervisors. Because the program is self-administered, supervisors require different numbers of hours to complete it. A study of past participants indicates that the mean length of time (μ) spent on the program is 500 hours and that this normally distributed random variable has a standard deviation (σ) of 100 hours. What is the probability that a candidate selected at random will take between 500 and 650 hours to complete the training program