Norm L. Logg, a graduate assistant, must design a coffee pot for the faculty that has a 90 percent chance of operating for 5 yr. (a) If the coffee pot failure times are lognormal, what should be the...

Norm L. Logg, a graduate assistant, must design a coffee pot for the faculty that has a 90 percent chance of operating for 5 yr. (a) If the coffee pot failure times are lognormal, what should be the MTTF? Assume that the shape parameter is 0.7. (b) If the coffee pot fails, it must be repaired within 4 hr or the faculty will suffer from caffeine withdrawal. If repair time is lognormal with a mean of 2 hr and a shape parameter of 1, what is the probability that the faculty will have their coffee on time? What is the most likely repair time (mode)?