5. (20 points) The acceleration frequency spectrum shown was taken in the horizontal direction on a gearbox near the pinion gear with 29 teeth, driving a 75-tooth bull gear. Power is supplied by a single-stage turbine operating at 3900 RPM with 12 vanes. Relate the frequency/order corresponding to each elevated acceleration amplitude to the problem it indicates. Identify the likely root cause of each problem, if possible. H. A, 113,100 1508 3900 111,592 114,608 46,800 110,084 3017 56,500 116,116 Frequency, CPM (not to scale)