The lifetime of a lightbulb in a certain application is normally distributed with mean μ = 1400 hours and standard deviation σ = 200 hours. a) What is the probability that a lightbulb will last more...

The lifetime of a lightbulb in a certain application is normally distributed with mean μ = 1400 hours and standard deviation σ = 200 hours. a) What is the probability that a lightbulb will last more than 1800 hours? b) Find the 10th percentile of the lifetimes. c) A particular lightbulb lasts 1645 hours. What percentile is its lifetime on? d) What is the probability that the lifetime of a light-bulb is between 1350 and 1550 hours? e) Eight lightbulbs are chosen at random. What is the probability that exactly two of them have lifetimes between 1350 and 1550 hours?