The time to complete a construction project is normally distributed with a mean of 60 weeks and a standard deviation of 4 weeks.
a) What is the probability the project will be finished in 58 weeks or less?
b) What is the probability the project will be finished in 66 weeks or less?
c) What is the probability the project will take longer than 65 weeks?
d) What is the probability that the project will be finished between 57 and 63 weeks?