On failure a part can either be replaced (and thus restored to as good as new) or be minimally repaired (and restored to operating condition). If it is replaced, the timebetween-failure distribution...

On failure a part can either be replaced (and thus restored to as good as new) or be minimally repaired (and restored to operating condition). If it is replaced, the timebetween-failure distribution is lognormal with a median time to failure of 1150 operating hours and s = 0.9. Minimal repair results in a nonhomogeneous Poisson process with rJ.t) = (0.4 x 1O^-8)(2.8)t^I.8. If a failure occurs at 400 operating hours, should the part be replaced if another 300 hr of use is required? Base your answer on the reliability over the next 300 hr.