On July 14, 2004, a power outage in the Northwest Airlines operations center near Minneapolis forced the airlineÂ's computer systems to shut down, leading to cancellation of 200 flights and delays in scores of other flights. (a) Explain how the concept of statistical independence might be applicable here. (b) How would the airline decide whether, say, expenditure of $100,000 would be justified for a backup system to prevent future occurrences?