dishwasher has a mean lifetime of 12 years with an estimated standard deviation of 1.25 years. Assume the lifetime of a dishwasher is normally distributed.

Round the probabilities to four decimal places.

It is possible with rounding for a probability to be 0.0000. a) State the random variable. Select an answer rv X = the mean lifetime of a sample of dishwashers rv X = the lifetime of a randomly selected dishwasher rv X = lifetime is normally distributed rv X = a randomly selected dishwasher rv X = the mean lifetime of all dishwashers Correct b) Find the probability that a randomly selected dishwasher has a lifetime of 8.65 years or more. Incorrect c) Find the probability that a randomly selected dishwasher has a lifetime of 13.75 years or less. Correct d) Find the probability that a randomly selected dishwasher has a lifetime between 8.65 and 13.75 years. Incorrect e) Find the probability that randomly selected dishwasher has a lifetime that is at most 8.875 years. Correct