Among fatal plane crashes that occurred during the past 65 years, 404 were due to pilot error, 91 were due to other human error, 538 were due to weather, 413 were due to mechanical problems, and 295 were due to sabotage. Construct the relative frequency distribution. What is the most serious threat to aviation safety, and can anything be done about it? Complete the relative frequency distribution below. Relative Cause Frequency Pilot error % Other human error % Weather % Mechanical problems % Sabotage % (Round to one decimal place as needed.) What is the most serious threat to aviation safety, and can anything be done about it? O A. Mechanical problems are the most serious threat to aviation safety. New planes could be better engineered